Question about 1985 Chevrolet Chevy

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90 chevy cuts off and idles up and down

When i take map sensor it idles fine but has no power. When i put it back on it idles rough but has some power. Both of them have hesitation

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Sounds like their is to much air getting to the engine. This is caused by an air leak in the vacume lines. Try replacing all the vacume lines on the engine.

If you have the vortec motor they are notorious for the fuel pressure regulator failing. Have the fuel pressure tested at the fuel rail. If it is below or at 56 the engine will have hesitation or rough odle and no power.

Please contact me if your problem presists.

Thanks, Charlie

Posted on Jan 30, 2009


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