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A bad spark plug, a bad spark plug wire, a bad distributor cap, a bad rotor, a bad fuel injector, the firing order is mixed up, a bad valve or a vacuum leak could cause your rough idle.

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โˆ™ 2010-02-19 21:12:59
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โˆ™ 2006-04-23 16:37:56

Vacuum leak is the most common cause.

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Q: What is cause of rough engine idle?
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Related questions

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I blown head gasket can cause an engine miss which one cause a rough idle.

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No, on a fuel injected engine it can cause high idle speed.

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There are many things that can cause a rough idle on this car. The computer could be going out, the engine may not have enough oil, and the engine may not be getting enough fuel or electricity.

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The most common reason for an engine not to start is a lack of fuel. A plugged air filter can cause and engine to idle rough or not idle at all.

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A faulty gas cap could cause the check engine light to come on but it would not cause a rough idle or engine noises. Start with having your local auto parts store read the codes. The codes will help determine why the check engine light is on.

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What can cause a 1195 Oldsmobile to idle rough?

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