Mechanical Inspection: Compression
Check engine mechanical condition using a compression gauge, vacuum gauge, or an engine analyzer capable of performing a relative compression test. See engine analyzer instruction manual for availability and description of relative compression feature.
CAUTION:
Use a remote starter to crank engine during compression test; DO NOT use ignition switch. Fuel injectors on many models are triggered by ignition switch during engine cranking. This could create a fire hazard or cause engine flooding, crankcase contamination, hydrostatic lock or lubrication to be washed from cylinder walls.
ENGINE COMPRESSION
| Application | psi (kg/cm2 ) | |
|---|---|---|
| Minimum Compression Pressure | ||
| 2.5L, 3.3L, 3.9L, 5.2L & 5.9L | 100 (7.0) | |
| 3.0L | 178 (12.5) | |
| Maximum Variation Between Cylinders | 25 (1.8) | |