my 2002 run good, but at a stop light the rpms go surge from 600 to 1200, bach and forth. put it in neutral and it idles right. any ideas?
Check for vacume leak,s at or around intake,and if engine light is on could be bad tps.
check engine/service engine soon or other dash lights. Spray some carb cleaner or starting fluid around your vacuum lines and listen for the idle to change this will help you find a leaking vac. line. (try to do this while the engine is cold & have a fire extinguisher handy just in case!).
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