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Home >> Saturn >> 2008 >> Astra L4-1.8L >> Repair and Diagnosis >> Engine, Cooling and Exhaust >> Engine >> Tune-up and Engine Performance Checks >> Compression Check >> Testing and Inspection
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Compression Check: Testing and Inspection



Engine Compression Test

Removal Procedure

1. Remove the throttle valve module.
2. Remove the spark plugs.
3. Remove the relay holder cover.
4. Remove the fuel pump relay.
Draw relay K3 out of mounting plug.



Measurement Procedure

Compression, Check

* 4 cylinder

Important: Engine revs at least 300/min.


* Start the engine (approx. 4 seconds).
* Compare the compression values.
Maximum pressure differential 100 kPa (1 bar)



Installation Procedure

1. Install the fuel pump relay.

* Place into the socket.
* Ensure the plug contacts are sound.

2. Install the relay carrier cover.
3. Install the spark plugs.
4. Install the throttle valve module.

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