Cutlass Supreme

Intake Manifold Gasket May Leak Coolant or Engine Oil on Oldsmobile Cutlass Supreme

Problem Description and Possible Solution

The intake manifold gasket may develop and external engine oil or coolant leak. In some cases, an internal coolant leak may occur causing coolant to mix with the engine oil. Our technicians tell us that operating the engine  with a coolant/oil mix can result in internal engine damage. Replacing the intake manifold gasket should correct these leaks.

Problem Data
RepairPal Verified
Average mileage: 136,163 (75,000–300,000)
Engines affected: 3.1L V6, 3.4L V6
5 model years affected: 1993, 1994, 1995, 1996, more1997
15 people reported this problem
Viewing 1 - 6 of 6 comments
Oil had gotten into the radiator and I began to burn the engine coolant and oil cause the engine to steam/smoke. I flushed the radiator out and refilled it with new engine coolant but now my car is misfiring and idles/takes off very rough.
Its also a good time to replace head gaskets at the same time. Its only a few more bolts to take off.
Started overheating quickly withing just 3-5 minutes of driving. Noticed the peanut butter color substance in the oil from the coolant and oil mixing. Lower intake gaskets on the 3.1 are notorious for blowing out, replaced it, problem solved.