Oil Cap Off...low idle?
#1
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Oil Cap Off...low idle?
I was checking my oil level today and noticed my idle (RPM's) did not decrease as I removed the oil cap. I remember this being true on my SC, Carrera and 964. Does this apply to 993's?
My idle is low (approximately 600) and does not stall. I do have a LWF and never experienced any stalling as well. When my AC is turned on, my idle does increase to where I feel the idle should be w/o it on.
I've checked vacuum leaks, hoses, etc... to confirm if I have a leak elsewhere. Car runs great and burns minimal oil. I have no CEL indicating any codes whatsoever!
So back to my original concern; should my idle drop when I remove the oil cap? Would this indicate a vacuum leak somewhere? Should I replace the oil cap?
My idle is low (approximately 600) and does not stall. I do have a LWF and never experienced any stalling as well. When my AC is turned on, my idle does increase to where I feel the idle should be w/o it on.
I've checked vacuum leaks, hoses, etc... to confirm if I have a leak elsewhere. Car runs great and burns minimal oil. I have no CEL indicating any codes whatsoever!
So back to my original concern; should my idle drop when I remove the oil cap? Would this indicate a vacuum leak somewhere? Should I replace the oil cap?
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some times removing the oil cap would create a vacuum leak...not sure on 911s but know this is true for my Audi RS4. Even the dip stick gasket going bad on the RS4 can cause a vacuum leak.
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This is not the case on the 993.
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I cleaned my ISV and even adjusted it a couple degrees.
However, as others mentioned here the ECU will just adjust it back to where the idle was prior.
The next thing I'll do is r&r caps and rotors, check plug wires and spark plugs.
Thanks for your comments!
However, as others mentioned here the ECU will just adjust it back to where the idle was prior.
The next thing I'll do is r&r caps and rotors, check plug wires and spark plugs.
Thanks for your comments!