Q: Rough idling - 1990 Chevrolet G30

asked by on September 28, 2016

My van overheated one time. After that, it started to idle rough. This occurs in reverse, park and drive when the engine is still cold. When the engine warms up, there would still be rough idling but only in reverse and drive, whereas it's fine in neutral or park. The van has no trouble accelerating. I checked the tailpipe and there is no resiude or moisture. The oil and coolant are looking good and aren't mixed. The spark plugs are fine as well. What should I do?

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This could be an issue with a blown head gasket. This would require a professional mechanic to check engine compression as well. This can occur without causing oil/coolant mixing. If you are still having trouble, a certified technician from YourMechanic can come to your home or office to definitively diagnose the rough idling issue.

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