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Rough Idle

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Old Aug 30, 2025 | 09:22 AM
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m_mclaughlin77's Avatar
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Default Rough Idle

I bought a 2002 corvette and took the engine out to replace some gaskets and clean it up a bit. After reinstalling, the car turns on easily, has good oil pressure, etc., but I am having a rough idle. The car seems to rev up a couple hundred rpm's and then drop off, almost cyclically. I noticed a leak around the engine valley where the knock sensors are so I am planning on replacing that gasket, but I don't think the rough idle is being caused by that. I don't have any codes on my car besides some misc codes like traction control.

Does anybody have any ideas?

Replaced the following:
Head gaskets
Valve cover gaskets
Upper and lower oil pan gaskets
Front main seal gasket
Oil pump
Timing chain
Rear main seal
Exhaust manifold gaskets
Spark plugs and wires

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Old Aug 30, 2025 | 06:41 PM
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It is always best to use a factory level scan tool but if you at least have a code reader you can record some data PIDS while at idle and let us know what you see…if no code reader find a diagnostic shop in your area..hard to diagnose this for you over the internet.
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