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Home >> Audi >> 1994 >> V8 Quattro V8-4.2L (ABH) >> Repair and Diagnosis >> Maintenance >> Tune-up and Engine Performance Checks >> Compression Check >> Testing and Inspection
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Compression Check: Testing and Inspection


1. Perform compression test with engine at operating temperature, spark plugs removed, oil temperature above 86°F and throttle plate completely open.
2. Disconnect coil high tension wire from distributor cap and connect to suitable ground.
3. Connect compression tester per manufacturers instructions, then crank engine until compression tester shows no further increase in pressure.
4. Compression should be 131-189 psi with a maximum difference of 44 psi. Minimum compression should be 102 psi.
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