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1991 Acura Integra Repair Question


Topics covered: Rpm, Engine, Ignition timing.
Mileage: 265,000 miles.

Asked on December 15, 2010

Engine "motorboating" at idle

The cold start idle is around 1400 RPM. With warmup the idle steadily "motorboats" between about 1050-1600/1700 RPM. Driving perfomance is excellent-the problem is just at idle. I have located the idle adjustment screw and it is screwed all the way in. As I adjust it out, the RPMs become higher by a factor of 400-500 RPMS at both ends of the range. A possibly related problem-in hotter weather the engine will not start after short stops, i.e. to run into a convenience store, etc. It seems to need to cool down a bit first. Maybe related, maybe not
Avatar Asked by rikmic

Answer

Replied on December 15, 2010

There are a few things to be checking here, make sure that there are no vacuum leaks, clean the IAC and the throttle plate, check ignition timing, check for any unresolved fault codes with a scan, start here.

mark (mhpautos)

Tiny Answered by mhpautos (expert)
26,892 answers provided