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YOUR RESEARCHHigh Idle and Now Check Engine Light
Leading reported evidence
Check oil cap so you can feel/hear any leak/sealing
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1
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Suggestion
You may want to turn on the engine first before you check the oil cap so you can feel/hear any leak/sealing when you twist/untwist the cap.
Leading evidence: 'Check oil cap so you can feel/hear any leak/sealing' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Check oil cap so you can feel/hear any leak/sealing' (1 discussions). For that action, 0 discussions report a resolution and 0 report an unsuccessful attempt. No action has an explicit, attributable resolution report under the current rules. These are forum reports and suggestions, not a confirmed diagnosis.
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2000 C4 Coupe
For the last few days the idle has been a bit high around 1100 after warmed up. Today, the Check Engine light came on.
Any thoughts in advance of taking it in to have the code checked. Can this code be checked at a local auto parts store or does it require a special reader?
Thanks!
Rudy
Yes, a generic obdii scanner from an auto parts store will do. There are 500+ error codes that can trip the CEL so it's hard to tell what is wrong without the codes. One potential cause of high idle is intake air leak but there are many other causes too.
Don't run the engine if the CEL starts flashing. Other than that I don't know what to suggest. If it was mine I would take it to Auto Zone and see what they suggest. If they didn't come up with a solution then I would ring the Porsche garage and ask questions. Good luck.
As others suggested, read the code. It doesn't sound like your light was flashing - but a flashing MIL is an indication that there is imminent possible danger to the emissions equipment (catalytic converters) - if it IS flashing, that's useful diagnostic info even before reading the codes. The single light merely indicates a fault exists that you should investigate - it is not cause to get excessively anxious.
A high idle could be a vacuum leak, a MAF sensor that needs cleaning or replacement, etc. - once you have the code, post it back. The code plus the behavior should give you a starting point of what to try.
If you have another car, I'd use it until you can read the code(s). Many codes self-clear if the condition is corrected, and you don't want to lose any potentially valuable diagnostic info.
Alright, got the code readout: P0507 - no surprise
P0507 - Idle Air Control System RPM Higher Than Expected
Funny thing is that I had my indy check and add a little oil the other day and I wonder if the cap is not on tight like in this thread -
https://rennlist.com/forums/996-foru...cel-p0507.html
I will check it tonight and update the thread. Thanks again.
You may want to turn on the engine first before you check the oil cap so you can feel/hear any leak/sealing when you twist/untwist the cap.
If you hear no difference with the cap tight and loose, your oil filler tube may be cracked.
This should be the final update. The OIL cap was indeed loose when I checked it. Put it on correctly and started the car with an initial 1100 RPM warm-up and then it settled into a comfortable and stable 900 RPM. Happy end.
Thanks again everyone!
R
