Engine Compression
Check engine compression with engine at normal operating temperature, all spark plugs removed and throttle wide open.
NOTE:
Compression pressure and cylinder pressure variation for 2.5L and 4.0L engines are not available from manufacturer at time of publication.
COMPRESSION SPECIFICATIONS
| Application | Specification | |
|---|---|---|
| 2.5L | ||
| Cherokee | 9.2:1 | |
| Wrangler | 9.1:1 | |
| 4.0L | 8.8:1 | |
| 5.2L | 9.1:1 | |
| Normal Compression Pressure | 120-150 psi (827-1034 kPa) | |
| Minimum Compression Pressure | 100 psi (689 kPa) | |
| Maximum Variation Between Cylinders | 5 psi (172 kPa) | |