Mechanical Inspection: Compression
Warm engine to normal operating temperature before checking the compression. Ensure battery is fully charged. Remove ignition coils and spark plugs. See IGNITION SYSTEM in REMOVAL, OVERHAUL & INSTALLATION article. Check engine mechanical condition with a compression gauge, vacuum gauge, or engine analyzer with throttle fully open. See engine analyzer manual for specific instructions. See COMPRESSION SPECIFICATIONS . Install and tighten spark plugs to 13 ft. lbs. (18 N.m).
COMPRESSION SPECIFICATIONS
| Application | Specification | |
|---|---|---|
| Normal Compression Pressure | ||
| ES300 | 218 psi (15.3 kg/cm2 ) | |
| GS300 & SC300 | 192 psi (13.5 kg/cm2 ) | |
| GS400, LS400 & SC400 | 178 psi (12.5 kg/cm2 ) | |
| LX470 | 192 psi (13.5 kg/cm2 ) | |
| RX300 | 218 psi (15.3 kg/cm2 ) | |
| Minimum Compression Pressure | ||
| ES300 | 145 psi (10.1 kg/cm2 ) | |
| GS300 & SC300 | 156 psi (11.0 kg/cm2 ) | |
| GS400, LS400, LX470 & SC400 | 142 psi (10.0 kg/cm2 ) | |
| RX300 | 145 psi (10.1 kg/cm2 ) | |
| Maximum Variation Between Cylinders | ||
| All Models | 14 psi (1.0 kg/cm2 ) | |