I am new to Mercedes, the one i just purchased has a couple of problems.. The first one being it will not high idle when COLD, i did see a thread about a a Cold Start Valve is this cleanable or do I need a new one... I see where it is, in the front of the air cleaner. Also the fuel pump runs continously is it suppose too???

Next would be it tends to idle rough and increase idle when in park position... It runs down the road great.. Idle control Valve I know but I can't seem to find it there are 2 black boxes and the overlaod relay (which by the way looks nothing like it should in pictures for replacement) One box say 5500 kickdown the other box closes to the reoverload relay just has numbers and no explanation...

I do have some spare parts from an older (1986 420 SEL but I'm scared to change out the boxes even though the numbers are close)

Thanks for your time..

Jerry....