» » »

Mercedes-Benz Q&A

Ask Your Question

1990 Mercedes-Benz 560SEL Question: will not stay idling

 

Question

sir kidd, Waverly Hall, GA, November 26, 2009, 14:11
 Rookie

The car runs good and strong but will not stay running unless the gas peddle is gently held its like it needs to be idle up i can hold the air intake flap down 1/4 inch and it will idle just find im just lost on it

2 Answers
Flag This
  • Medium-star Best Answer
    Bret Bodas from RepairPal Test Shop, November 30, 2009, 10:54
     Master

    These vehicles have a mechanical fuel injection system that is very susceptible to vacuum leaks. There are also some adjustments that need to be performed in a sequential order for everything to operate correctly, so if you're not familiar with how the system works, you may be better taking this to a MB shop. However, here are some tips.
    Check for vacuum leaks, especially at the injector seals. Fix any you find and make sure the fuel mixture is set correctly. This engine has an idle valve that controls the idle speed, it may be that the valve is sticking or bad. Also, check that the throttle body is cleaned and adjusted properly.

    Reply
    Flag This
  • Answer #2

    Visitor, June 27, 2010, 17:57

    Check the fuel pressure relay, it must be seated very snug in the socket. Most times this the problem

    Reply
    Flag This