Engine Compression
To check engine compression, bring engine to normal operating temperature. Disconnect cold start injector (if applicable). Disconnect distributor electrical connector(s). Remove all spark plugs. Remove air intake hose from throttle body, and fully open throttle. Measure at 250 RPM as quickly as possible.
COMPRESSION SPECIFICATIONS
| Application | Specification | |
|---|---|---|
| Compression Ratio | ||
| ES300 | 9.5:1 | |
| LS400 & SC400 | 10.0:1 | |
| SC300 | 10.2:1 | |
| Compression Pressure | 178 psi (12.5 kg/cm2 ) | |
| Minimum Compression Pressure | 142 psi (10.0 kg/cm2 ) | |
| Maximum Variation Between Cylinders | 14 psi (1.0 kg/cm2 ) | |