Compression Check: Testing and Inspection

HAZARD WARNINGS





WARNING:

Risk of injury when hood opened and engine running.
The engine is equipped with an electronic ignition system. Because of the high ignition voltage, it is extremely dangerous to touch any of the ignition components (ignition coil, distributor, ignition cables, spark plug connectors, test socket) when:
^ The engine is running.
^ The engine is started.
^ The key in the steering lock is in position 2 and the engine is being cranked by hand.

Pay attention to notes regarding working on breakerless transistorized ignition system!

PROCEDURE





Engine
Warm up to normal operating temperature.
Spark plugs:
Remove.
Install.
Engine:
Crank several times to eliminate residues and soot (refer to Engine, Service and Repair, Cranking Engine With Starter) by pressing at contact handle of compression pressure recorder (01) in closed throttle position and parking brake applied.
Diagram sheet (03):
Insert into compression pressure recorder (01).
Compression pressure recorder (01) with adapter (02) and sealing cone (04):
Press in into spark plug hole of relevant cylinder.
Model 140:
Throttle valves
Open fully by means of accelerator pedal.
Engine:
Crank with starter approximately 8 revolutions.
All cylinders:
Test In the same manner.
Spark plug recesses:
Blow clean with compressed air.
Fault memory of DI control module (N1/4 and N1/5):
Read fault memory (see Powertrain Management).
If minimum compression pressure not achieved test cylinders for leaks (Refer to Engine, Testing and Inspection).





NOTES:
Model 129: Test cylinder 12 with 90° adapter (05) because of fuel lines.
Model 140: Test cylinders 6 and 12 with 90° adapter (05).


TEST DATA





SPECIAL TOOLS