The upper intake manifold gasket and/or a PCV vacuum lines/hoses can develop vacuum leaks with age. This type of leak can result in a higher that normal or rough idle.
Average mileage: 120,000 (120,000–120,000)
Engine affected: 3.1L V6
1 model year affected: 1990
3 people reported this problem
Verified for the Chevrolet Celebrity1 report
1 answerAugust 01, 2013
1 answerMay 02, 2015