I have an 87 300e The car will some times start hard when it is warm. It will miss and sputter, then clear out and run fine. It has new plugs, the cap and rotor are in good shape, and I put a new fuel filter on and this has changed nothing. I think It could be the idle controll valve, because it dosn't happen all the time, and only when it's warm. How do you check the valve is my frist question and what else could it be? Where should I look next

Thanks guy's

The idle valve would be about last in the things I would worry about.

The idle valve is a automatic throttle with a very small capability. The way you would test your theory would be to use your foot to open the main throttle and see if that made some difference.

More likely, you have an injector or two leaking down or a residual fuel pressure problem.

__________________
Steve Brotherton
Continental Imports
Gainesville FL
Bosch Master, ASE Master, L1
33 years MB technician

Thanks I'll check in to that, One other thing I did not mention is that somtimes it will idle rough, or when I take off for a stop the car will have a lot less power than normal. Once again this is not all the time. My idle will somtimes be 550 or as hight as 1100?

Now that COULD be an idle control problem, but not likely hard starting or rough running. Only the lack of stable idle speed.

__________________
Steve Brotherton
Continental Imports
Gainesville FL
Bosch Master, ASE Master, L1
33 years MB technician