What happens to the engine rpm when idle?
At idle, on an intermittent basis, the rpm repeatedly sur… While idling, my rpm will surge from about 1100 to 1700 over the time frame of a second or two then return to 1100 over that same time frame, then repeat. If I put a load on the engine by turning on the airconditioning compressor, the surging will often stop.
What causes intermittent stalling in a car engine?
More Causes. One of the more unusual causes of intermittent stalling we’ve heard about is a defective vehicle speed sensor. When the vehicle stops moving, the PCM may not engage the idle speed motor (carbureted engines) or idle air bypass motor (fuel injected engines) so the engine will idle normally.
Why does the engine surging stop at idle?
If I put a load on the engine by turning on the airconditioning compressor, the surging will often stop. This is an intermittent problem but seems to occur at least 50% of the time and seems to be worse after the engine has warmed up. Thank you for any input. My car has 225000 miles. My car has a manual transmission.
Why is the throttle valve not working at idle?
There a few things that can cause this situation on your car. The most common have to do with the throttle body and the idle air control system. The throttle body is the where your your throttle valve is housed. The throttle valve is connected to the gas pedal via a cable.
Can a stalling engine be intermittent driveability?
Intermittent driveability problems of any kind are always a challenge to diagnose. When a customer brings you a vehicle and complains of a stalling problem, you may not have much to go on other than their description of what’s happening and when it happens.
Is there an intermittent engine cut out in a van?
Yes, the van starts right up again with no problem other than it gets pretty hairy in mid-turn trying to shift into neutral and crank the engine all the while trying to turn the steering wheel without power. I sprayed the throttlebody last night with trottle cleaner which seems to have helped, but it’s too soon to tell for sure.
What makes an engine run and idle without stalling?
Every engine needs three things to run and idle smoothly without stalling: a correct air/fuel ratio, sufficient idle speed for the idle load, and a good spark. If any of these is lacking, the engine may stall. Cold stalling problems are the most common because the engine needs a richer fuel mixture to maintain idle speed until it warms up.
Is there check engine light for intermittent stalling?
Many times, there will be no check engine light and no fault codes to give you a clue as to what might be causing the engine to stall. So the trick to diagnosing an intermittent stalling problem is to catch the vehicle when it’s acting up — and that rarely happens when you have the vehicle in your shop.
How do you reset the gas pedal on a Mercedes?
Press and hold the gas pedal for at least five seconds. Keep the pedal pressed. Turn ignition off but do not remove the key. Now release the gas pedal. Remove key. Wait a minute before you restart your Mercedes. This allows resetting the High and Low points of the gas pedal.
Is there a problem with the throttle sensor on a Mercedes?
Mercedes-Benz throttle body or throttle position sensor found on C-Class, E-Class, S-Class, CLK-Class, SLK-Class may fail causing idle issues, no idle or poor acceleration. Symptoms of defective Mercedes throttle body or throttle position sensor include:
If I put a load on the engine by turning on the airconditioning compressor, the surging will often stop. This is an intermittent problem but seems to occur at least 50% of the time and seems to be worse after the engine has warmed up. Thank you for any input. My car has 225000 miles. My car has a manual transmission.
At idle, on an intermittent basis, the rpm repeatedly sur… While idling, my rpm will surge from about 1100 to 1700 over the time frame of a second or two then return to 1100 over that same time frame, then repeat. If I put a load on the engine by turning on the airconditioning compressor, the surging will often stop.
Press and hold the gas pedal for at least five seconds. Keep the pedal pressed. Turn ignition off but do not remove the key. Now release the gas pedal. Remove key. Wait a minute before you restart your Mercedes. This allows resetting the High and Low points of the gas pedal.
When to replace the throttle possition sensor on a Mercedes Benz?
If you determine the throttle position sensor has failed on your Mercedes-Benz you will need to address this problem right away. In most cases, you will get code P0120 or P012x. Your options are to replace it with a new throttle position sensor.
What causes the idle quality to go down?
The build up of carbon can have adverse affects on idle quality. The most likely cause of your problem is the idle air control valve (IAC). The IAC is the most common part that fails on your particular car and is often gummed up with carbon as well.
What causes the idle air control valve to fail?
The most likely cause of your problem is the idle air control valve (IAC). The IAC is the most common part that fails on your particular car and is often gummed up with carbon as well. It has a couple mounting locations that I can’t be exact about unless the car were in front of me.
What does it mean when your car engine is hissing?
As with any out-of-the-ordinary sound emanating from your car or truck engine, hissing should be investigated ASAP. Left alone, things like this can come back to haunt you when that little sound turns into a big system failure and leaves you stranded on the side of the road. A hissing sound is usually not good, but don’t panic yet.
There a few things that can cause this situation on your car. The most common have to do with the throttle body and the idle air control system. The throttle body is the where your your throttle valve is housed. The throttle valve is connected to the gas pedal via a cable.
Why is my Volkswagen Golf running rough at idle?
Really, your Golf will be running rougher at any RPM, but a misfire will be most pronounced at idle. Spark Plug Wires – While not every model and engine combination of vehicles today comes with spark plug wires (a lot are now coil on plug), if your Golf happens to have them, they can go bad and cause a rough idle.
What are the symptoms of a bad fuel pressure regulator?
The symptoms are very noticeable, too. You may notice a very rough idle, rough acceleration, slow acceleration, and vibrations from the engine. There are also many causes of engine misfires. It can be a problem in the spark plug or the ignition coil.