E220 W124 Will Not Idle

[Hammer&Chisel]

My 1995/6 E220 (W124, 111.960) Automatic will not idle. This occurred suddenly and immediately after a car wash. Before the wash it worked fine, after the wash it didn't.

She starts, but one needs to keep the accelerator slightly depressed and hold it in a bit to keep it going. With the accelerator slightly depressed she idles smoothly, no judder or hiccups or such, but release the accelerator and the car cuts out. There are no warning lights on when the engine is running. She is impossible to drive like this unless one uses the left foot to brake and keeps the right foot holding accelerator down.

I have dried the engine bay out and let it stand for a day, but same thing happens. I have checked all the wiring that I can trace and it all looks intact and not cracked.

Any ideas what could be causing this?

 

[Vlad]

These suffer from the electronic throttle body failing.....one of the symptoms being that they will not idle and keep stalling.

 

[grober]

My 1995/6 E220 (W124, 111.960) Automatic will not idle. This occurred suddenly and immediately after a car wash. Before the wash it worked fine, after the wash it didn't. ---------------------
I have dried the engine bay out and let it stand for a day, but same thing happens.
Any ideas what could be causing this?

I take it from this the engine compartment was pressure washed-------VERY BAD IDEA!!!!

Chances are the throttle body or associated wiring has been damaged/shorted by water ingress BUT sometimes the throttle plate gets gummed up and cleaning the throttle body throat and edges of the throttle plate with solvent will restore idle function.