349 BHP

Okay ..
My RPM drops below 500 at idle and rises to 1,200 ... it feels like the car is about to stall when it drops but then the engine is keeping itself alive by lifting the RPM pass 1000. The shop i went to today, told me the fuel injectors needed to be cleaned. So, they cleaned it, but problem is not solved. They also said it's not the alternator. Anyone know?

I appreciate anyone's help!

MB-JIM

When I had the rpm dropping on my 92 400E it was the engine wiring harness. Once the harness was replaced everything was fine.

349 BHP

How much was the part and labor?

MB-JIM

I can't really say what it will cost for your car. If you search the subject I have seen the harness from $500 to over $700. It's not a big job to install but I would imagine most shops would charge at least 2 hours. They probaly use a flat rate book so you need to find out how many hours are shown for that job. I was with my independent shop mechanic when he installed the harness and it didn't take much over one hour.

349 BHP

I was just reading this:
http://www.mercedesshop.com/wire_har...20_harness.htm

I would do it myself but my car is already at the shop. I'll see what's happening tomorrow. Thanks jim!

Bobenis

That is 100% your Idle Control Valve. All you need to do is remove and clean it with carb cleaner or 99% rubbing alcohol. Allow the cleaner to sit in it and soak...shake it a bit but soak it for 20 min or so then drain and repeat...after put it back in. Clean the tubes that attach to it on either side as well. They as well as the ICV get gummed up. Once you have cleaned it, it will run perfectly. I just did mine on my '89 300TE with the same symptoms but it's perfect now. Once in awhile it needs to be done. My old Saab was the same way. The ICV is right under your air cleaner housing (needs to be removed off the intake). If you cant find it, I can take a pic of it tomorrow for ya and post it. Cheers

349 BHP

I dont think my car has an idle control valve
It's a 1994 E320 btw. The check engine light is on.