mattypv50

Hi All,

Wondering if you all might point me in the right direction.

911SC - When I start it up after sitting over night it fires right up, then RPMs drop to probably 400-600 (doesn't stall) and then after 3-4 seconds picks up to 1000-1100RPM and I drive right off. First stop sign within seconds and RPMs are fine. It's just that first start for a 3-4 seconds.

I've attached a pic of the car idling when warm - does this seem low to you? I'm wondering if the idle speed is too low across the board.

When I take the oil cap off the engine drops in RPMs so I don't think there is a vacuum leak.

I can live with this but wondered if there was something you all thought.

Thanks.

theiceman

odd that i just posted on pelican today with an almost identical issue on cold starts..
you could still have a tiny vac leak is what i was told. just because you make a bigger one with the oil cap means nothing.

coomo

Usual fluctations in CIS is an airleak.The system was a marvel when it was first launched.However, its complicated and regular maintainence vital.Personally Its always taken me a smoke test to find any tiny air leaks,Obviously check
all hoses for visible cracks first.If no air leaks are present,Id be checking pressure valve & metering head piston one may be sticking.

stlrj

Seems quite normal to me and hardly worth obsessing over.