How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Marty Your Own Question
Marty, Mercedes Technician
Category: Mercedes
Satisfied Customers: 53943
Experience:  Bosch Certified Master Tech. Over 35 years experience.
Type Your Mercedes Question Here...
Marty is online now
A new question is answered every 9 seconds

This is a question for Marty as he already knows the problem

Customer Question

This is a question for Marty as he already knows the problem I'm having. I have 1000 rpm once the engine is warmed up. Runs excellent otherwise. I used the troubleshooting guide you provided thank you. I confirmed that there is just under 400millamps going to the plug on the idle air control valve. If so it should idle at 650. I pulled the idle switch plug and the rpms went up. I grounded the oil temp switch and again the rpms went up. I'm assuming that all of this equipment is fine including the idle speed control electronics. Is it the idle air control valve? Should I look at adjusting mixture? Or is my dashboard tach defective?( I don't think it is as idle seems too high when I put it in gear.)
Submitted: 9 months ago.
Category: Mercedes
Expert:  Marty replied 9 months ago.

Hi Rick, at this point it can be either the valve or the control unit. I would try a new valve first.

Customer: replied 9 months ago.
Do you know where I can order one from?
Expert:  Marty replied 9 months ago.

You are going to have to shop for a used on in the salvage yards or on ebay. The part number is ***** 141 12 25. If you do a search on ebay you will find them for around $350. A new one is $1250 if they are still available.