Service Engine Light On and Idling Rough

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SPWALTERS
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I have a 2000 Oldsmobile Silhouette with 113,500 miles, 3.4L, automatic transmission. The engine overheated and the fuel pump and intake manifold valve was replaced. A month later, the Service Engine Light came on and the car was idling rough. Had the fuel pump replaced and a tune-up. Service Engine Light came back on and it was still idling rough. Found that the intake manifold gasket was leaking, which was replaced. Service Engine Light came back on and it still idles rough. If I allow it to idle for a few minutes, revving up to 2,000 rpms, car runs better. Now I am being told it could be a warped head gasket. Any ideas?
Sep 14, 2007 at 10:17 AM
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SERVICE WRITER
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A head gasket problem is always a fear when the engine is overheated.

Was a compression test or cylinder leak down test done?
Sep 14, 2007 at 11:43 AM
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SPWALTERS
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The invoice shows that a pressure test for leaks was done when they flushed the cooling system. This was done when the water pump was replaced, but not after the intake manifold gasket was replaced two months later.

The code for the Service Engine light shows a misfire in cylinder 2 each time. Should I have the spark plug replaced?
Sep 21, 2007 at 9:13 AM
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SERVICE WRITER
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You can check the compression test on it, cylinder leak down
can try a spark plug, can try a wire.

How old are the plugs and wires?

A misfire can be a wide range of possiblilites, but I would want to rule out compression as a problem based on the shop diagnosis.
Sep 21, 2007 at 10:08 AM
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SPWALTERS
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Spark plugs new as of early August. Thanks for the advice!
Sep 21, 2007 at 2:34 PM