causes for 500-1000 RPM fluxtuation at idle?
05-14-2016, 09:52 AM
#1
Racer
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causes for 500-1000 RPM fluxtuation at idle?
This may be a common occurrence and possibly caused by a few things but any suggestions as to a good place to start looking would be appreciated. 05 Boxster with 94K miles. Replaced MAS and oil separator recently but it was doing that before I replaced those.
05-14-2016, 01:35 PM
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Do you have a check engine light? One thing that will do that is if the oil cap is not tight enough or the seal is bad. These engines pull a vacuum in the crank case unlike older engines. If you have a vacuum leak you get miss fires and bad idle. Hey check the easy things first.
05-16-2016, 09:48 PM
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When I hear vacuum leak, I envision a small rubber tube that has come loose somewhere on the engine. Is there a more logical approach to finding a vacuum leak on a 05 Boxster?
05-19-2016, 01:34 PM
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Well, its not the oil cap. Strangely, this occurs:
When I have my foot on the clutch depressed, the RPM fluctuation occurs (like at a stop light). However, when I take it out of gear and release the clutch, the fluctuation goes away....steady rpm. What could be causing that??
When I have my foot on the clutch depressed, the RPM fluctuation occurs (like at a stop light). However, when I take it out of gear and release the clutch, the fluctuation goes away....steady rpm. What could be causing that??