Question about 1993 Nissan 300ZX

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High idle; 1500-2000 rpm; suspect idle control module?

Heard that they can be removed and cleaned but is it a practicle solution or should replace. Also heard that leaking fuel injector seals can create similar problem and even more costly to fix?

Problem existed when i got the car @ 125K miles. Did timing belt kit due to no history on the car. Installed cam angle sensor. Not sure how to set ignition timing. I am sure there are several things to the procedure. No manuals available. I did pay $50 for a wiring schematic. 10% of the color/stripe codes were in corrrect.

Thanks... Chuck H.

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First I would look for a vaccum leak. Many times a high idle can be the result of this. Just listen for a hissing sound while the engine is running. Sometime it may even be a cracked vaccum line and you can't hear hissing. Use some WD-40 or carb cleaner and spray around the suspected area or hose. If the engine slows down for a minute when you spray you've found the leak.

Posted on Feb 09, 2009

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Correct code P0504?


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This diagnostic procedure supports the following DTC:
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