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Old 02-11-2011, 10:48 PM
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Flug540 Flug540 is offline
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Location: Hayward, CA
Join Date: Nov 2009
Posts: 606
Mein Auto: 1998 BMW 540i 6-spd
Originally Posted by Mercutio2511 View Post
what process are u using to check the compression ratio of ur engine?
Umm OP i always open the throttle all the way when im checking for compression ratio..and the engine temperature is a factor...and the oil...and i always disable the fuel injection system too..
That's what I do too:

- Let the engine run until the operating temperature is reached;
- Remove DME relay;
- Remove all ignition coils/spark plugs;
- Attach the gauge;
- Crank the engine 6 times with the throttle open all the way;

Wet test is done the same way except a teaspoon of oil is added to the cylinder before the gauge is screwed in.
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