idle control valve?
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1990 Mercedes-Benz 500SL Question: idles very fast,starts hard
Answer #1jpincharge from JP Motors LLC, May 03, 2011, 10:31Technician
There should be an overload protection relay in the right front engine area by the firewall, check to see if fuse is blown or failed relay, this will affect both of your problems. Jump starting the vehicle with high voltage or crossed cable usually cause this type of problem.
Answer #2Superbob May 03, 2011, 10:33Master
More likely an unmetered air leak into the engine. Look for loose air intake duct clamps, a tear in the intake ducting, etc. It's possible that the IAC is faulty, but if that were all it is, I'd think the engine would start easy, Unmetered air would cause hard starting.
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