Engine Compression Test
WARNING: This page is about a different car, the 2003 Saturn Vue. However, it is still accessible from the selected car via links, so may be relevant.
Perform the following steps in order to conduct a compression test for the L61.
- Conduct the following steps in order to check cylinder compression.
- 1.1 Engine should be at room temperature.
- 1.2 Disconnect wiring from the ignition module.
- 1.3 Remove the spark plugs.
- 1.4 Throttle body valve should be wide open.
- 1.5 Battery should be at or near full charge.
- For each cylinder, crank engine through four compression strokes.
- The lowest reading cylinder should not be less than 70% of the highest.
- No cylinder reading should be less than 689 kPa (100 psi).
IMPORTANT: The results of a compression test will fall into the following categories:
- Normal - Compression builds up quickly and evenly to specified compression on each cylinder.
- Piston Rings - Compression low on first stroke. Tends to build up on following strokes but does not reach normal. Improves considerably with addition of oil.
- Valves - Compression low on first stroke. Does not tend to build up on the following strokes. Does not improve much with the addition of oil. Use approximately three squirts from a plunger-type oiler.