Mechanics

ROUGH IDLE

1994 Plymouth Laser

Engine Mechanical problem
1994 Plymouth Laser 4 cyl Front Wheel Drive Automatic 60000 miles

After the car warms up, the engine has a rough idle. The engine speeds up for once second, then, slows down for one second, and on and on. How do I fix this?
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Carman5000
December 24, 2009.



You may have a vacuum leak, get a can of spray gumout, spray the vac lines and maniflod area, when the idle changes, youve found the leak! You want the engine running and spray on the outside but do direct the stream onto the hoses, if it is a vacuum leak, the engine idle will change speed, then you have detected a leak, repair the vacuum leak and see how it runs! If that doesnt do it, you may need a new idle air control valve, it's bolted to the throttlebody

Merlin2021
Dec 24, 2009.


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