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Old 05-24-2003, 02:02 AM
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sixto sixto is offline
smoke gets in your eyes
Join Date: Jun 2000
Location: SF Bay Area
Posts: 18,746
Sounds like a bad idle speed controller. It's a stepper motor that cycles a valve to allow just the right amount of air at idle. When it gets tired and worn, it can't cycle fast enough or within a tight enough translation so you get a noticeable oscillation in idle speed.

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