the lawn mower does not idle

Causes

Trimmers are reliable and durable (provided they are properly maintained, of course). Most often, malfunctions occur due to contamination of structural elements.

If the motor of your lawn mower does not start, does not pick up speed, does not reach the power you need, or suddenly stalls, the reason may be:

  • low-quality fuel (fuel mixture), the case may be in long-term storage or in non-compliance with the recipe for preparing the mixture;
  • grass is wrapped around the shaft of the fishing line / knife;
  • clogged air filter / muffler;
  • unbalanced carburetor.

Troubleshooting methods

The first three reasons are fairly easy to eliminate. If the matter is in the mixture, you need to pour out the old fuel from the tank, prepare a new emulsion from high-quality gasoline and engine oil (if your engine requires a mixture) and pour it into the fuel tank. If the trimmer is running on clean gasoline, it’s even easier.

In the second case, it is necessary to carefully free the trimmer parts from the wound grass.

If the filter is clogged, you can try rinsing it. If this procedure does not bring any effect, replace it with a new one.

The last reason a lawn mower doesn’t work properly will require a little more knowledge and skill from you.

To properly adjust the carburettor for lawn mowers, a specific procedure must be followed. First, clean the air filter thoroughly. The easiest way is to rinse it (it is advisable to douse the filter with water regularly after 9-10 hours of operation).

After that, in the diagram of your trimmer, which is in the instruction manual of the device, find the adjustment screws. There are usually three of them: the first is responsible for fuel supply, the second is for idling, and the third is designed to limit the number of maximum engine speed.

Next, turn on the unit and wait for the engine to warm up.

Tighten the first (fuel mixture) adjusting screw slowly. Catch the moment when the motor starts to stall and turn the propeller back 45 degrees. If you did not have time and the motor stalled, the screw should be turned 90 degrees. Open the throttle and watch the revs increase. Next, slowly unscrew the screw (each turn is the same 45 degrees) until the moment when, at full throttle, the engine begins to firmly give out maximum revolutions.

The second screw, as mentioned above, controls the engine idle speed. By loosening it, you decrease the number of revolutions, while twisting it, you increase it. The screw needs to be adjusted so that the motor runs reliably at low revs. For better starting, speed up the engine slightly. At the same time, make sure that the motor rotates several tens of times before starting the movement of the knives / line reel. If the engine starts poorly, tighten the screw a little.

After you have adjusted the first two screws, test the operation of the unit at maximum engine speed. If necessary, you can limit it (maximum). this will protect the motor from “boiling”. To do this, you need to tackle the third screw. Unscrew the locking nut until the adjusting screw can be safely turned. To increase the maximum number of revolutions, the screw must be loosened, to decrease. on the contrary, tighten. Fix the position of the screw with a nut. Test the motor again.

Check the position of the screws regularly. the high vibration levels of lawn mowers can cause them to move unintentionally.

Remember that carburetor adjustment is not a final procedure. During the operation of lawn mowers, you will most likely have to tinker with it more than once, because an unbalanced carburetor means both increased fuel consumption and a quick failure of the candles, not to mention a decrease in the power and performance of the device.

The gasoline trimmer is not gaining momentum: the reasons and features of the repair

It is not necessary to purchase an expensive and bulky lawn mower to cut grass on a small lawn; it can be easily replaced by a gasoline / electric trimmer. The device of these machines is quite simple, they are easy to use and unpretentious in maintenance. But sometimes problems do occur. One of them. when the trimmer does not develop the maximum number of revolutions. will be discussed in this article.

Little tricks

  • If you are unable to tighten / loosen the adjusting screws properly, it may be that the spring is too thick and stiff. Then you can choose instead of her a more suitable.
  • If your unit does not need pure gasoline, but its mixture with engine oil, strictly observe the proportions specified in the operating instructions. There is one little thing: the recommended ratio is 1: 25 (for all brands of oil) or 1: 50 (for “native” oils). Try the first ratio first. If, with such a recipe, oil drips appear on the motor, and a strong carbon deposit forms on the candle, reduce the proportion of oil by half. This usually helps to fade traces and reduce the amount of carbon deposits.
  • To clean the spark plug electrodes from combustion products, you can use fine-grained “sandpaper”. Wipe them down with a dry cloth first and then gently sand them with sandpaper. If the space between the body of the device and the insulator is also clogged, a regular unbent paper clip can help clean it. To do this, briefly soak the candle in diesel fuel, and then scrape off the dirt. If the blockage is small, one procedure is sufficient. In case of heavy dirt, it is sometimes necessary to repeat it several times. After complete cleaning, the candle must be wiped dry from the remaining diesel fuel, and then it can be used as directed.
  • Please note that foreign-made lawn mowers (gasoline, electric or battery) require a little more maintenance than domestic ones. In particular, many strongly recommend entrusting the adjustment of the carburetor of a two-stroke engine to professionals, especially if your purchase has not expired the warranty period.
  • And finally, one more tip: follow all the manufacturer’s recommendations for the operation and maintenance of the device. This will prolong its smooth operation.

You will learn more about what to do if the petrol trimmer is not picking up speed.

What to do if the chainsaw does not idle?

Idling problems are considered constant companions of chainsaws. There may be several prerequisites that could lead to slugs at the time of starting and spinning of the circuit during idle operation, the main of which are:

  • clogging of the air and gasoline filter;
  • poor-quality fuel mixture or improper preparation;
  • malfunctions of the ignition module;
  • a carburetor whose settings have ceased to correspond to the load on the saw;
  • the propulsion elements are deformed or rusted.

A number of actions are sequentially performed:

  • flush the fuel hose or replace it with a new one,
  • clean the air filter, which could be clogged with sawdust and dirt particles. Modern air filters are reusable, they can be washed with the addition of detergent, completely removing them from the saw body;
  • check gasoline and engine oil, which may be of poor quality or simply not suitable for working with this saw;
  • test candles and carburetor.

Eliminating one or more possible faults usually returns the saw to its former strength.

The chainsaw is not gaining momentum: a review of the reasons and do-it-yourself repairs

Malfunctions occur both with expensive German or American modifications of chainsaws, and with their cheap Chinese fakes. It’s nice when the moment of starting the motor tool goes smoothly: the saw warms up and gradually reaches the rated power declared by the manufacturer, which is issued throughout the entire working cycle. Things are worse if everything happens the other way around: after pulling on the gas cable, the unit starts to slip, it works in jerks after short pauses, stalls and starts up again from the pusher.

There can be many reasons for this phenomenon, as well as scenarios for the development of events. Let’s consider in detail each working situation and breakdowns that preceded them.

The chainsaw does not develop speed: we test the device for malfunctions

The ignition module can be diagnosed for problems visually. For this you need:

  • turn out the candle;
  • evaluate its appearance (it should not be drenched in gasoline or contain a black coating);
  • check the distance between the coil and the magnets (up to 0.2 mm);
  • if necessary, examine the spark plug unit for spark supply using a working mains wire.

If, after checking, no defects were found, it is worth moving on to checking the carburetor block.

This work unit is one of the most vulnerable in modern chainsaws. New tools, which are shipped from the factory, have basic settings. for low and high speeds, which must be reset after running-in and running-in of all parts. Similar actions are performed if the saw does not develop traction corresponding to the maximum torque according to the instructions.

In this case, you need to reconfigure one of them. the “H” jack, which is responsible for the operation of the saw under load. To do this, it is enough to adjust the fuel supply with the engine running at the highest speed of rotation of the chain using a tachometer and operating instructions.

Why the chainsaw isn’t picking up steam?

Launching is a complex multi-level process that involves almost all of the saw’s life support systems. That is why the fact that the saw loses speed, turns on intermittently and feels confident exclusively at idle speed should be considered from different angles.

Such factors could lead to this:

  • a faulty motor. its service life could be exhausted, and the piston rings and cylinder could wear out, deform or even corrode;
  • a failed spark plug or the coil itself. as a result, the spark required to ignite the air-fuel mixture is not generated;
  • unbalance of the carburetor screws, as well as a number of reasons that could disable it.

Other chainsaw malfunctions

A lot of users are faced with a nuisance when the chainsaw does not slow down. The device reaches maximum power in a matter of seconds, which cannot be reduced.

This may be due to the fact that:

  • the throttle valve does not function. its spring or thrust element has weakened;
  • the toggle switch does not switch well;
  • the throttle shaft has lost its corkscrew.

But the opposite can be the case. when the saw is gaining power uncontrollably. The reasons why the chainsaw itself is gaining momentum should be sought in:

  • carburetor. it needs to be cleaned or readjusted;
  • fuel supply system. gas filter, fuel hose;
  • malfunctions of the cylinder-piston or branch pipes connecting them to the carburetor.

There are a lot of breakdowns that manifest themselves through revolutions atypical for a particular part of the working cycle. But an attentive attitude to the instrument will help diagnose them in time and return it to normal operation.

Diesel stalls at idle

The problems of gasoline internal combustion engines described above, associated with working on the XX, are not about Bosch and diesel engines. A frequent malfunction of diesel engines is a malfunction of the high-pressure fuel pump (injection pump). Natural wear of the plunger pairs, the presence of impurities in diesel fuel or air leakage of the injection pump leads to the fact that the diesel starts up and then stalls.

READ  Self Repair Lawn Mowers

The gasoline engine does not idle

To begin with, this malfunction indicates two possible causes: failure of individual mechanisms, assemblies or sensors, as well as severe contamination of certain elements. Both in the first and in the second case, it is necessary to carry out diagnostics. The engine on injection and carburetor cars can most often stall at idle in such cases:

If the car immediately stalls or the revolutions noticeably float after the starter is turned off, then you should pay attention to the throttle assembly. The option of both clogging of the damper and wedging of the mechanism is possible. This malfunction, especially heavy pollution, occurs as a result of a long drive on fuel of poor quality, as well as untimely replacement of the air filter.

In this case, the throttle valve must be cleaned. To clean the throttle, a conventional “carbikliner” (carburetor cleaner) is used, and it is also necessary to blow out the damper using compressed air from the compressor. If these actions did not help, then you will need to assess the condition of the oil trap. This element is an integral part of the engine crankcase ventilation system. Contamination of the oil catcher leads to the fact that blow-by gases “choke” the engine, idle speed floats and the internal combustion engine stalls.

Now let’s look at a situation where the car starts up normally, but then starts to stall (constantly or at regular intervals). A similar situation often occurs on injection cars that have an electronic engine control system (ECM).

For car owners that have been in operation for a long time, it is advisable to have these sensors in stock, as well as a multimeter for self-diagnosis. This is especially necessary if the car is often used for long journeys on the highway. Note that most of these sensors have an acceptable cost.

Another important point is that the car may start to stall at idle after flashing the ECU. Unprofessional correction of the factory firmware, flashing or chip tuning of the electronic engine control unit can lead to malfunctions. Although the motor after such actions demonstrates the best return under load, at high speeds, etc., in parallel, the unit is not able to operate normally at 750-800 rpm. In this case, the installed firmware should be adjusted to achieve stable operation of the internal combustion engine in all modes.

Now a few words about the carburetor. The engine often stalls on such engines precisely because of the contamination of the jets and the long absence of proper carburetor adjustment. The fact is that even small particles of debris in the fuel can disrupt the operation of the carburetor injection. Dirt can be contained both in low-grade gasoline and enter the system from a gas tank, in which deposits gradually accumulate.

This agent is a solvent cleaner in an aerosol can. As for the mechanical fuel pump of carburetor engines, this type of pump has a filter screen. The specified element can also become clogged, reducing the performance of the pump. The membrane of a mechanical fuel pump can also fail. In parallel with wear, diaphragm particles clog the channels in the carburetor.

With the injection system on the injector, the situation is more complicated. If replacing the ECM sensors does not help, then you should start checking the intake manifold for excess intake air, and also exclude air in the fuel system. Then you need to go on to check the injection nozzles, measure the pressure in the fuel rail, inspect the vacuum hoses, etc. Special attention will be required to the vacuum brake booster. We also add that regardless of the type of injection (engines with an injector or carburetor), it is necessary to check the ignition, spark plugs, high-voltage wires, the distributor coil and other elements of the system.

Motor stalls at idle

The situation when the engine stalls at idle occurs quite often. This phenomenon can manifest itself both on cars with high mileage and on new cars. It is worth noting that the process of starting a cold engine with a starter can be both initially difficult and completely normal.

In other words, the engine can start well “cold” or “hot”, but then starts to stall at idle. Also, in some cases, it appears that when you press the gas pedal and increase the speed, the engine starts to work stably. There are several main reasons why the engine “does not keep” idling, troit and shakes. Next, we will consider why the car stalls at idle or runs very unevenly after starting “cold”, in transient modes “hot”, etc.

What is the bottom line

Finally, we add that fuel lines, connections and hoses are rubber products. For this reason, it should be remembered that natural aging of rubber occurs. On cars that are more than 10 years old, cracking of rubber hoses becomes a frequent occurrence, which leads to air leaks. It should be added that the external condition of such hoses is not an accurate indicator of their condition. The inner surface of the walls also collapses, which leads to particles invisible from the outside into the injector, carburetor or high-pressure fuel pump, especially in cases of a problem in areas behind the fuel filter.

The main reasons why the engine starts to stall after warming up. Frequent problems of carburetor and injection engines, fault diagnosis.

The car engine starts and stalls immediately after starting: the main causes of this malfunction. Diagnosis of possible causes, tips and tricks.

As a result, jerks and dips appear when gaining speed, the car jerks in motion in transient modes. Causes and troubleshooting.

Floating cold engine idle speed. Major malfunctions, symptoms and breakdown detection. Unstable idling of a diesel engine.

The reasons why, after pressing the gas pedal, failures occur and the engine begins to swell. Engine failures with LPG when switching from petrol to gas.

Why the engine can have increased idle speed. The main reasons for high XX revolutions on an injection engine and engines with a carburetor.

Does not idle the chainsaw

The serviceability and efficiency of household and professional chainsaws largely depend on the degree of wear and tear of their main operating mechanisms. Several factors indicate damage to the working units of the gasoline tool, the main of which is the speed of the running engine. Their arbitrary growth or decrease can prompt the operator about a breakdown of the carburetor, violation of the clutch clearance and other malfunctions. this will allow to identify any of the breakdowns in time and eliminate it on their own.

The chainsaw does not slow down. how to find and fix a breakdown?

The most common cause of this frequent breakdown is an improperly adjusted damper. It is needed to suck in the air that the carburetor needs to enrich the fuel mixture with air. To adjust the choke, you need to adjust the operation of the carburetor. In this case, special attention should be paid to the operation of the power unit at idle. You can check the operation of the engine in idle mode by paying attention to the state of the circuit immediately after starting the internal combustion engine. If it rotates, then you need to adjust the power unit.

Another reason for this typical malfunction is air leaks. If air leaks in one of the chainsaw mechanisms, the mixture will automatically deplete, which will lead to a spontaneous increase in the speed of the chainsaw motor. In this case, the operator will need to carefully check the entire fuel system, including the carburetor, pipes, and working chambers of the unit.

In some cases, the chainsaw does not decelerate due to a jammed accelerator cable. In this case, the power unit will independently gain momentum to the maximum immediately after it is started. Disassembling the gas handle and inspecting the entire gas supply mechanism will help to solve the problem. A jammed cable will need to be adjusted or completely replaced.

Why the chainsaw isn’t picking up steam?

In cases in which the used gasoline saw is not able to steadily gain momentum and stalls spontaneously when you press the accelerator, you will need to carefully check the engine crankcase and carburetor. First of all, the operator should carefully inspect the assemblies and make sure that they are not sealed. If a large amount of oil was found inside the crankcase or carburetor, then the leak inside the faulty unit must be repaired.

The next reason why the chainsaw does not develop speed. a manufacturing defect or mechanical damage to the breather located inside the fuel tank. A vacuum can form in the fuel tank, which leads to a lack of fuel supply to the working cylinder of the power unit. Deposits that have accumulated on the surface of the fuel cylinder can also cause this problem. In this case, you need to remove the filter element and rinse it in clean gasoline. If after that the chainsaw continues to stall under load. then you need to perform the following procedure: turn off the power unit of the chainsaw, remove the fuel tank cap and tighten it again. If after that the motor of the gasoline-powered tool starts to gain momentum and after 5 minutes of operation it stalls again, then the cause of the breakdown is a faulty breather.

A thick layer of carbon deposits on the walls of a factory muffler can be another common cause of a saw motor not spinning. Resinous deposits and ash will prevent exhaust gases from escaping, which will lead them back to the engine compartment. As a result, the engine will begin to emit extraneous sounds and severely lose speed even with a slight press on the accelerator.

What to do if the chainsaw is gaining momentum by itself?

This malfunction is typical for novice gardeners who ignore the need for timely maintenance of their gas powered tools. In the case of an arbitrary set of revolutions with a chainsaw, the cause must be sought in the carburetor. First of all, it will need to be completely disassembled. After making sure that all the built-in parts are in good working order, you can start flushing the fuel unit. For this you need:

  • place all carburetor elements in a container with clean gasoline. After knocking, the parts must be removed, rinsed thoroughly with water and dried;
  • the fuel pipes must be blown out with compressed air from a cylinder. Immediately before re-installing the hoses at the points of their connection to the fittings, you will need to apply silicone sealant;
  • after installing the carburetor, not the chainsaw, you need to re-adjust it. Before that, you need to make sure that the power unit is in good condition, as well as the filters, rubber gaskets and bushings are in working order.

In some cases, the cause of an arbitrary set of revolutions with a chainsaw may be a loss of sealing of the crankshaft oil seal. Due to constant contact with the moving shaft, the stuffing box lends itself to increased heating, which leads to the formation of cracks and holes inside it. A damaged gasket cannot be repaired, so it must be replaced.

Often the cause of air leakage, due to which an arbitrary set of revolutions by the motor occurs, is the loss of fixation of the bolted connections. In this case, the operator will need to tighten all the bolts and check the operation of the gasoline tool again.

repairing bad idle on a briggs and Straton 4 5hp

The chainsaw does not idle. search for reasons and repair

There can be several reasons for this common breakdown. Basically, the loss of revolutions when the internal combustion engine is idling is associated with engine malfunctions, loss of compression in its standard cylinder, ignition system, carburetor, as well as improperly prepared fuel mixture. In search of the exact cause of a breakdown, the operator may encounter the following problems:

  • accumulation of resinous deposits and ash, small debris on the air and fuel filters of the chainsaw. if possible, the elements must be washed. If, in addition to blockages, cracks or holes were found on the surface of the filters, then the foam rubber elements will need to be completely replaced;
  • spark plug defect. cracks, chips or burrs disrupt the work of the part, which leads to a loss of engine speed when the engine is idling. In this case, the candle will need to be replaced;
  • loss of factory settings of the carburetor. increased pressure on the power unit leads to an increase in its vibration. As a result, the spring-loaded metal bolts of the fuel assembly lose their original position, which leads to a loss of engine speed;
  • cracks and holes in the fuel pipe. to repair the chainsaw, the hose must be replaced;
  • clogging of the inner walls of the muffler. dismantling, thorough flushing and reinstalling the muffler will help solve the problem. If large burrs have formed on the internal cavities of the element, then it will soon begin to rust. To prevent this, it is better to replace the muffler immediately;
  • malfunction of the CPG of the power unit. the appearance of microcracks or burrs on the inner surface of the cylinder and piston will lead to a loss of tightness of the working chambers. As a result, the amount of air required to enrich the fuel mixture will be disrupted. this will result in a loss of engine speed when idling.
READ  How to connect a mower to a tiller

The stable operation of a chainsaw engine largely depends on the quality and proportion in which the fuel mixture is prepared. An excess or lack of oil will lead to a gradual deterioration in the performance of the power unit and over time it will not be able to work even at idle speed. To prevent this, you need to strictly adhere to the ratio of gasoline and oil, which is indicated in the instructions for the chainsaw used.

Possible reasons that the engine stalls at idle speed

Errors in the operation of the XX regulator. In modern cars, such a regulator is performed:

  • according to the bypass scheme with control of the bypass air supply channel bypassing the throttle valve;
  • throttle valve angle control;
  • regulator in the fuel pump.

To accurately determine the reason for stopping the power unit, computer diagnostics are required.

Fuel supply interruptions. Such malfunctions are most often associated with:

  • clogging of the fuel system and filter;
  • wear of the fuel pump;
  • low rail pressure.

First of all, it is necessary to check the pressure in the fuel rail with a pressure gauge.

Ignition misfires, internal combustion engine triplets. This is usually associated with critical wear of coils, candles, high-voltage wires.

Sensor errors in the control system of the power unit, electrical equipment. The most “influential” in the internal combustion engine are the crankshaft, camshaft, and mass air flow sensors. An autoscanner is required for error control.

Air leaks into the intake manifold system, intercooler. In this case, an incorrect composition of the combustible mixture is formed, which leads to malfunctions of the engine.

Poor quality fuel. This problem is especially common in diesel engines. At low temperatures, the fuel can wax. As a result of this process, the pressure in the rail decreases, the engine may stall.

Problems with carburetor engines

The idle system in the carburetor is the most sensitive to dirt. Therefore, if the carburetor engine stalls at idle, it is worth blowing out the jets and channels of the XX system, and on cars with electronically controlled forced idle, it is also worth checking the operation of the economizer solenoid valve. On Solex carburetors (VAZ 2108-2109), the idle fuel jet is put on the solenoid valve stem, and in the absence of voltage across the valve, it is closed. To make sure that the valve is to blame, on these carburetors, it is enough to unscrew it slightly to remove the pressure of the jet against the body and allow fuel to flow past the closed jet. Is the idle speed stable? This means that either the EPHH unit does not supply voltage to the valve (which is checked by a light bulb or a tester), or the valve itself is inoperative.

There are not many reasons why the valve control unit may not supply voltage to it. In addition to a malfunction of the unit itself, this is a loss of power on pin 4, a break in the connection with the ignition coil (the EPHX unit stops “seeing” the engine speed), the absence of a “mass” on the carburetor limit switch (pin 5) when the gas pedal is released.

Note that a common problem with carburetors is the tight relationship between the composition of the air-fuel mixture from the vacuum and the fuel level in the float chamber. If any of these parameters change, the composition of the mixture will “float away” as well. It will go beyond the limits of a normally flammable one. if the car does not keep idling until it warms up, then the mixture is depleted, if the car stalls on hot, then re-enrichment already occurs.

lawn, mower, does, idle

A change in the vacuum at idle is a consequence of air leaks through the vacuum lines (for VAZ it is more often a vacuum brake booster or a vacuum distributor corrector) or a violation of the tightness of the carburetor-manifold joint. Here “Solex” has a long-known disease with warping of the mating plane of the hull, “Ozones” in this regard show themselves better.

Ignition on carburetor cars in the overwhelming majority of cases is distributor, except for two-cylinder engines, where it is enough to use a two-lead coil without distributing the spark supply. If the motor stalls, and does not troit, then the problem is hidden until the spark is distributed. see the breaker contacts, the central high-voltage wire, the carbon contact connecting the cover and the slider.

Problems with spark plugs are common with both carburetor and injection engines. This is natural wear and tear, which under normal conditions proceeds evenly, sooner or later all the candles in the set will start working intermittently, and carbon deposits due to poor-quality fuel or a violation of the composition of the mixture (over-enrichment, carbon black carbon deposits disable the candles). Iron-containing additives (the notorious ferrocene) can kill candles in one unsuccessful refueling. So you should immediately pay attention to the candles, especially if access to them is not difficult.

Why does the injector stall at idle?

A plus of VAZ injection systems, which were first installed on the 2110 family, and then on the continuation of the genus “eight”, slightly updated externally 2114-2115, is that they are simple in design, and as a general example of injection system malfunctions are most evident.

The injection ECU has feedback algorithms and affects the idle speed both coarsely (using the idle speed controller or “electronic” throttle) and subtly (by varying the ignition timing), so it is more difficult to make the injection engine stall. In addition, the rejection of the distributor and the installation of either a dual ignition module (eight-valve models) or individual coils (sixteen-valve motors) also increased the reliability of the ignition system: at least on two cylinders, but the engine will work. Air leakage has also become less critical. The turns will start to float, but if the idle turns are gone, then the reason is hidden in another.

One of the most likely culprits here is significant contamination of the injectors. The four-nozzle nozzles of eight-valve motors are sensitive to dirt: their flow area is the same as that of the two-nozzle nozzles of 16-valve motors: the area of ‚Äč‚Äčeach individual hole is half the size, and it is easier to clog it. There are cases worthy of anecdotes: on an excessively clogged fuel filter, the pressure developed by the gas pump is enough to break the filter curtain, and the flow of fuel will carry the accumulated dirt into the fuel line and rail. This is likely for motors with a drain ramp, where a fine filter is located before the pressure regulator, and the fuel flow from the pump passes through the filter. For engines with a drainless ramp, the pressure is cut off even in the fuel pump module, and only the amount of fuel that is consumed by the injectors flows through the filter.

With dirty nozzles, mixture formation is disturbed due to a change in the shape of the spray pattern, and the mixture itself can deplete beyond the range of stable ignition. The injection ECU has a margin for correcting the opening times of the injectors to compensate for their clogging, but this margin is not unlimited.

Leaking injectors can become a problem: due to the constant flow of gasoline into the inlet, the candles become overgrown with carbon deposits and filled with gasoline, which immediately affects the stability of the idle. The more carbon deposits accumulate on the spark plugs, the more difficult it is for the engine to operate. However, in case of leaks that can cause the engine to stall, the enrichment of the mixture is immediately noticeable by the characteristic black smoke and “lumbago” in the muffler.

The same enrichment of the mixture is created by a faulty mass air flow sensor. The author has repeatedly come across sensors that show an air flow rate several times higher than normal. At the same time, the engine still worked somehow when the gas pedal was pressed at increased speeds, but at idle with a loud burst from the muffler and clouds of black smoke it finally stalled. The “haste” check is known to everyone: disconnect the connector from the mass air flow sensor to force the injection computer to switch to an emergency program for calculating the cylinder filling by throttle position and rpm. The mixture will then come within an acceptable range.

And malfunctions in the idle speed actuators can cause problems. A jammed idle speed control in the closed position (and it closes completely each time the ignition is turned on so that the injection computer sets a zero reference point for IAC control) can prevent the engine from operating when the gas pedal is released. The “electronic” throttle has problems with the servo drive to exclude the possibility of maintaining the operation and operation of the pedal, since there is no direct mechanical connection between the pedal and the throttle.

Another reason for problems with idle running that is difficult to catch without diagnostic equipment is hidden in the position sensor and its reference crown, which is cut into the crankshaft pulley at VAZ and also has a damper. Damper wear causes beating and deviation of the crown position: at idle, when the signal amplitude from the DPKV is minimal, the DPKV processor may miss impulses. in this case, the engine control unit will lose the ability to correctly determine the rpm and fuel supply points and sparks, after which it will block the ignition and fuel injection.

But the oscilloscope immediately detects the problem. in the above illustration, you can see that the signal amplitude changes periodically. With such a violation of the DPKV signal, problems with idle are already possible.

Something else useful for you:

Why does the car stall at idle?

This malfunction is common for engines, from old carburetor engines to modern injection engines; both gasoline and diesel engines are sick with it. Analyzing the possible reasons for the extremely unstable idling, we will take the well-known VAZ models for clarity, and only for diesel engines we will have to make an exception.

Common problems on all motors at idle

As you know from the old adage, the engine does not work if there is nothing to ignite, or there is nothing to ignite. Idle conditions are most severe for gasoline engines with quantitative mode control. Throttle valve closed.

The volume of air entering the cylinder is minimal, the pressure is also minimal. the fuel mixture is supplied just enough for the engine to rotate.

The oscillogram of the pressure in the cylinder, even at slightly increased revs, gives us a pressure peak just above 5 bar. And this, mind you, is a serviceable engine, which has a hot compression of 13 bar. Now imagine what the pressure will be on a cold one when the pressure loss through the piston rings is greater. Therefore, since ancient times, almost the first thing they look at when a car stalls at idle is the state of the engine. Compression measurement, even with a rough mechanical pressure gauge, accurately determines how worn out the cylinder-piston group or valve. In high-powered engines, the possibility of errors in setting the tags of the gas distribution mechanism was added to the wear. Where the GAZ-69 works quietly when the camshaft gear is shifted by a tooth, a more modern engine is no longer able to keep idling.

READ  Lawn Mower Knives: Requirements, Varieties, Features of Attachment And Selection

Excessive pressure losses in a worn out engine during the compression stroke can only be compensated for by increasing the air supply. The revolutions have to be maintained with the gas pedal, but starting the engine will be a whole ritual, since at starting speeds the peak compression pressure is even less than at idle.

Compression is even more important for a diesel engine. By heating the air that is compressed in the cylinder, the fuel injected by the injector is ignited. At the same time, the regulation of the regime in diesel engines is qualitative, not quantitative: as much air enters the cylinder as it can draw in, only the volume of injected fuel changes. But due to the fact that at idle the compression stroke time is the greatest, with a loss of tightness (wear of rings, burnout of valves, losses through the cylinder head gasket), the highest loss of compression pressure will be at idle, and a diesel engine that normally operates at increased speeds, when released the gas pedal can also start to stall.

We must not forget about the quality of the fuel itself: it often happens that problems begin after refueling. over, the emergence of network gas stations did not reduce the scale of the problems, rather the opposite: if earlier it was possible to protect oneself from an outspoken “leftist” without stopping at openly suspicious gas stations (for example, in his city, the author quickly learned where to refuel, where it is impossible, and where. only if it is urgently needed), but now refuellers of large network companies regularly supply car services to car services that stubbornly refuse to work: it is enough to throw diesel fuel into the gas tank by mistake instead of the “ninety-second”, and even the unpretentious UAZ-469 will start working intermittently.

Why the engine does not keep idling and stalls

Troubleshooting sequence

If the effect of stopping the engine at XX appears, the following work must be performed sequentially:

  • full car diagnostics, with decoding of all error codes;
  • replacement of faulty sensors, assemblies and modules, the failure of which is indicated by the diagnostic results;
  • control of fuel pressure in the rail;
  • search for the possible presence of a suction in the intake system;
  • flushing the throttle valve and XX regulator assemblies with a special agent;
  • check of components of the ignition system;
  • replacement of the fuel and air filter;
  • fuel draining and refueling with high-quality fuels and lubricants.

The scooter does not idle and stalls

The scooter does not idle. the main reasons

Consider a situation where the scooter starts, but does not idle. The engine strives to stall.

Of course, this is a clear sign of piston wear and a catastrophic drop in compression, so you first need to make sure the engine is in good working order. In general, any troubleshooting with the engine, you need to start with measuring the compression. If the piston is worn out, you will never be able to carry out high-quality diagnostics and return to normal engine performance.

It should be noted that further we are not considering floating idle, namely the impossibility of the scooter idling after starting. That is, when the scooter starts up, it will idle a little (even if it is 2 seconds) and stalls. If the rpm floats, but the engine does not stall, this is the place for you. why idle rpm float.

lawn, mower, does, idle

Now, in fact, the reasons.

Why the scooter does not idle and stalls

  • Check the screws for mixture quality and idle speed. The quality screw should be unscrewed 1.5 turns and the idle screw to normal speed. at the same time, the engine should respond well to idle speed adjustments by increasing and decreasing rpm.
    Oddly enough, but in most cases, when scooters come to our workshop with a complaint. “does not keep idling”, we just make adjustments using screws for 1 minute and the problem is solved.
    Important: adjustment should be made only after the engine has warmed up, when the starting enrichment closes the channel, we talked in more detail about adjusting the carburetor here. how to properly adjust the carburetor.
  • Make sure the starter enrichment is working properly. Without its adequate work, the cold scooter engine will not keep idling. How to check it correctly, we considered here. checking the starting enrichment on a scooter.
  • If the compression is normal, and when adjusting the idle speed with the screw, there is no reaction from the engine, most likely dirt has got into the idle jet. The carburetor must be removed and cleaned. It is important to do this correctly, by unscrewing the nozzles and completely purging all channels. How to properly flush the carburetor, we discussed here. At the same time, check the starting enrichment.
  • Dirt could also get into the channel of the starting enrichment.
  • Check valve clearances if the scooter is four-stroke. How to do this correctly, we talked here. how to set up the valves on a scooter.
  • Some Chinese switches can distort the ignition, then the engine also stalls, while it works extremely unstable for several seconds. If you have previously replaced the switch, pay attention to this.

You can also check out other articles on the topic:

Normal operation of the scooter at idle speed depends on many factors, including the condition of the piston, spark plug, carburetor, air filter, muffler, switch, hall sensor, etc.

In order to find out for sure the cause of the unstable idling of your scooter, it is necessary to carry out a series of operations to identify the breakdown and make decisions for troubleshooting.

Let’s start checking. Adjust the idle speed of your scooter, watch what happens next. Let’s consider three possible developments of events point by point:

Even after tuning, the scooter engine runs at high revs. First, you need to make sure that the throttle valve of your scooter is fully closed to prevent gassing. If the damper is not fully closed, check the adjustment of the gas control cable (damper) and adjust the cable properly.
However, if the throttle is closed, and the rpm is still high and cannot be adjusted, it is necessary to check the idle jet in the carburetor for compliance with the required marking, namely, the required diameter for a particular scooter model.
2. The scooter works unstable at idle, despite the manipulation of the setting. In this case, initially you need to check the ignition timing for compliance with the standards. If deviations are found, the switch, the hall sensor, the wiring must be checked.
If the ignition timing is normal, the first step is to pay attention to the gap between the spark plug electrodes. If the gap does not correspond to the nominal, it must be determined as such, and if the gap and the plug are normal, the composition and quality of the fuel mixture, regulated by the carburetor, must be checked.
3. The scooter does not idle despite numerous attempts to adjust the idle speed. In this case, the first thing to look at is compression. In the absence of normal compression, it is simply unrealistic to achieve a stable idle.
If the compression is found to be very low, make sure your scooter’s CPG is tight, check all gaskets and bolt tightness. Check piston rings for wear.
If the compression is still normal, switch to the idle jet. In such cases, it is often clogged with dirt, which means that cleaning the carburetor is simply necessary here.
Even if after cleaning the carburetor it is not possible to achieve idling of the scooter, be sure to check the fuel level in the float chamber and, if necessary, adjust.
In that case, if the problem has not been resolved, it is necessary to inspect the carburetor mount, making sure that there are no various damages. The vacuum tube of the fuel cock and the plate valve are also subject to inspection.

In this article, you will find answers to the following questions:
Why does a scooter stall at idle.
Why is there no idle on the scooter?
Why does a scooter stall at idle speed.
Why the scooter doesn’t idle.
Why the scooter won’t idle.
Why does a scooter stall at idle.

Normal operation of the scooter at idle speed depends on many factors, including the condition of the piston, spark plug, carburetor, air filter, muffler, switch, hall sensor, etc.

In order to find out for sure the cause of the unstable idling of your scooter, it is necessary to carry out a series of operations to identify the breakdown and make decisions for troubleshooting.

Let’s start checking. Adjust the idle speed of your scooter, watch what happens next. Let’s consider three possible developments of events point by point:

  • Even after tuning, the scooter engine runs at high revs. First, you need to make sure that the throttle valve of your scooter is fully closed to prevent gassing. If the damper is not fully closed, check the adjustment of the gas control cable (damper) and adjust the cable properly.
    However, if the throttle is closed, and the rpm is still high and cannot be adjusted, it is necessary to check the idle jet in the carburetor for compliance with the required marking, namely, the required diameter for a particular scooter model.
  • The scooter works unstable at idle, despite the manipulation of the setting. In this case, initially you need to check the ignition timing for compliance with the standards. If deviations are found, the switch, the hall sensor, the wiring must be checked.
    If the ignition timing is normal, the first step is to pay attention to the gap between the spark plug electrodes. If the gap does not correspond to the nominal, it must be determined as such, and if the gap and the plug are normal, the composition and quality of the fuel mixture, regulated by the carburetor, must be checked.
  • The scooter does not idle, despite numerous attempts to adjust the idle speed. In this case, the first thing to look at is compression. In the absence of normal compression, it is simply unrealistic to achieve a stable idle.
    If you find that the compression is very low, make sure your scooter’s CPG is tight, check all gaskets and bolt tightness. Check piston rings for wear.
    If the compression is still normal, switch to the idle jet. In such cases, it is often clogged with dirt, which means that cleaning the carburetor is simply necessary here.
    Even if, after cleaning the carburetor, it is not possible to achieve the operation of the scooter at idle, be sure to check the fuel level in the float chamber and, if necessary, adjust.
    In that case, if the problem has not been resolved, it is necessary to inspect the carburetor mount, making sure that there are no various damages. The vacuum tube of the fuel cock and the plate valve are also subject to inspection.

Briefly, the process of finding the cause of the lack of idling on a scooter can be observed in the following diagram:

As a rule, after all the considered manipulations, it is possible to restore the normal idling operation. Do not forget also about adjusting the valves on a four-stroke scooter, regularly checking the air filter and cleaning it in time.