Mechanical Inspection: Compression
Warm engine to normal operating temperature before checking the compression. On non-turbo models, disconnect electrical connectors at fuel injectors before checking compression. On turbo models, disconnect electrical connectors at camshaft position sensors and fuel injectors before checking compression. Camshaft position sensors are located on intake manifold side of cylinder head. See Figure.
On all models, remove ignition coils and spark plugs. See REMOVE/INSTALL/OVERHAUL article. Check engine mechanical condition with a compression gauge, vacuum gauge, or engine analyzer. See engine analyzer manual for specific instructions. See COMPRESSION SPECIFICATIONS table. Install and tighten spark plugs to 13 ft. lbs. (18 N.m).
COMPRESSION SPECIFICATIONS
| Application | Specification | |
|---|---|---|
| Normal Compression Pressure | ||
| Non-Turbo | 192 psi (13.5 kg/cm2 ) | |
| Turbo | 156 psi (10.9 kg/cm2 ) | |
| Minimum Compression Pressure | ||
| Non-Turbo | 156 psi (10.9 kg/cm2 ) | |
| Turbo | 128 psi (9.0 kg/cm2 ) | |
| Maximum Variation Between Cylinders | ||
| All Models | 14 psi (1.0 kg/cm2 ) | |