having brain farts on tune up problems

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May 12, 2006 | 01:50 PM

redc3

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Melting Slicks

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From: pr, frederick md.

having brain farts on tune up problems

can anyone suggest what makes my car run on after turning it off? the wierd part is it will only do it every third or fourth run!?!? i am a fair tuner and this car runs extremely well other than this occasional bug. the only odd thing ive done is cut back the electrodes on the plugs. could this cause run on?
383, 525. cam, airgap, headers, 850 double pump demon
thanks in advance
jack

May 12, 2006 | 02:06 PM

lars

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From: At my Bar drinking and wrenching in Lafayette Colorado

Jack -
Run-on is normally a high idle issue. If you can, drop your idle speed down.

GM had a problem with this, and solved it by using the idle-up solenoids. You could always find an old idle-up solenoid and install it to fix the problem.
Lars

May 12, 2006 | 02:18 PM

redc3

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Melting Slicks

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From: pr, frederick md.

i dont know man. my car idles around 650, 700 rpms. i cant adjust any lower because it bogs down to much when the fans come on. any other old/odd things you can think of that cause intermitent run on? are my shortend plugs staying hot and igniting leftover fuel? im outta ideas

May 12, 2006 | 02:45 PM

lars

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From: At my Bar drinking and wrenching in Lafayette Colorado

The plugs would have to be glowing red hot like a glow engine glow plug, and I really doubt that's happening... When GM couldn't solve the problem with run-on by lowering idle rpm, they installed idle-up solenoids. Just install a solenoid and fix the problem.