Compression check how to
Melting Slicks
Joined: Sep 2006
Posts: 2,736
Likes: 7
From: Redding CA
Pop out one spark plug, have someone crank the engine over...watch the gauge and not the reading..
You can also test for leak down on each cylinder using a compression gauge but I don't know the specified amount of time you're supposed to wait until seeing how much has bled off...
You can also test for leak down on each cylinder using a compression gauge but I don't know the specified amount of time you're supposed to wait until seeing how much has bled off...
Thread Starter
Drifting
Joined: Feb 2011
Posts: 1,826
Likes: 1
From: Plymouth Wisconsin
St. Jude Donor '11-'12
What do you need to do to cut off fuel so the car doesn't start. Are the plugs really easy to get to. Im going to have someone take a look at a car for me that's why im asking
Racer
Joined: Feb 2010
Posts: 491
Likes: 2
From: AZ
2. Turn over the car to relieve fuel pressure.
3. Remove all the plug wires and plugs.
4. Thread in the compression tester.
5. Crank engine until you get a reading.
6. Move to next plug and repeat from step 4.
BTW, you may as well install new plugs while your at it. I'm partial to the Autolite 764, but plug choice is up to you.
Don't forget to anti-sieze the thread of the plugs and coat the top in dielectric grease, even if you're reusing the old plugs.
Finally, don't forget to put the fuel pump fuse back in when you're done.
Last edited by mx597turbo; Mar 2, 2011 at 05:21 PM.
Pro
Joined: Apr 2008
Posts: 628
Likes: 4
From: Columbia SC
I've always removed all the plugs before compression-testing each cylinder in turn. Lot less load on your starter and you get a quicker reading. But not having done this on a C5 maybe there is some reason not to?
Le Mans Master
Joined: Nov 2005
Posts: 6,993
Likes: 25
