Mechanical Inspection: Compression
WARNING: This page does not describe the selected car, but rather 7 other vehicles, including the 1990 Jaguar XJ6, 1990 Jaguar XJ-S, 1989 Jaguar XJ6, 1989 Jaguar XJ-S, and 1988 Jaguar XJ6. However, it is still accessible from the selected car via links, so may be relevant.
Check engine mechanical condition with a compression gauge, vacuum gauge, or an engine analyzer. See engine analyzer manual for specific instructions.
WARNING:
DO NOT
use ignition switch during compression tests on fuel injected vehicles. Use a remote starter to crank engine. Fuel injectors are triggered by the ignition switch during cranking mode, which can cause a fire hazard, or contaminate the engine's oiling system.
COMPRESSION SPECIFICATIONS
| Application | Specification | |||||
|---|---|---|---|---|---|---|
| Compression Ratio | ||||||
| XJS | 11.5:1 | |||||
| XJ6 | 9.6:1 | |||||
| Compression Pressure | ||||||
| XJS (1) | 200-220 psi (14.1-15.5 kg/cm2 ) | |||||
| XJ6 (2) | 160-170 psi (11.2-12.0 kg/cm2 ) | |||||
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