Emsflyer84

Hey all, my 01 E430 4matic started revving high 2200rpm on cold start. Almost as high on warm start. It never used to do this. Seems like it would be bad for it to rev so high on start. The idle comes back down to normal 600 or so. Then after driving and putting it back in park, it idles around 1000 rpm from that point on when in park or nutural. Idle only comes down to normal when put in gear.

This problem went away for a few days but just came back.

Any thoughts? Thanks!

Plutoe

Nothing is simple on a Benz--the elements of your cars(113.940) idle speed control consist of the ECU, intake air temp sensor(on your car built into the MAF), engine coolant temp sensor, accelerator pedel sensor and the throttle valve actuator.

Now without the diagnostic tools how are you going to determine which sensor is sending bad data to the ECU.

Additionally we know that the car should idle at around 1500 for a short period of time when the coolant temp is less that 40C

Now you know the system---go find someone with the diagnostics to stop you from making bad parts purchasing decisions