Engine Compression

WARNING: This page does not describe the selected car, but rather 14 other vehicles, including the 1991 Pontiac Sunbird, 1991 Pontiac Grand Prix, 1991 Pontiac Grand Am, 1991 Pontiac 6000, and 1991 Oldsmobile Cutlass Supreme. However, it is still accessible from the selected car via links, so may be relevant.

Check engine compression under the following conditions: engine at normal operating temperature and specified cranking speed, all spark plugs removed, and throttle wide open.

COMPRESSION SPECIFICATIONS

Application

Specification

Compression Ratio

2.0L (VIN K)

8.8:1

2.2L (VIN G)

8.9:1

2.3L (VIN A & D)

9.5:1

2.5L (VIN R & U)

8.3:1

Normal Compression Pressure

⁽¹⁾

Minimum Compression Pressure

⁽¹⁾

⁽¹⁾	The lowest compression reading should not be less than 70 percent of the highest compression reading. No cylinder compression reading should be less than 100 psi (7 kg/cm² ).