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Want to do Compression check

Old Jul 1, 2007 | 02:15 PM
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Default Want to do Compression check

I was wanting to do a compression check and I was wondering what the best way to disable the ignition is?
Old Jul 1, 2007 | 05:46 PM
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What I would do is pull the two harnesses off of the CAS.
Old Jul 1, 2007 | 05:48 PM
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The cas only has one harness that i know of.

Pull the connectors off the coils and pull the fuel injection fuse in the fusebox. Hold the throttle to the floor.
Old Jul 1, 2007 | 10:17 PM
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I just pull the wires for the injector harness and coils.
Old Jul 2, 2007 | 09:25 AM
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unplug the cas
Old Jul 4, 2007 | 09:00 PM
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Can somebody please explain to me what the heck is goin on here ?
I thought that you'd need some type of measuring equipment to do a compression check ?
Old Jul 4, 2007 | 10:07 PM
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Originally Posted by Fergus
Can somebody please explain to me what the heck is goin on here ?
I thought that you'd need some type of measuring equipment to do a compression check ?
Yes, A compression tester. However to use the compression tester you need to crank the engine, you don't want fuel and spark when you are cranking it just to test compression.

Everyone above is describing ways to cut fuel and spark.
Old Jul 4, 2007 | 10:24 PM
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Originally Posted by Fergus
Can somebody please explain to me what the heck is goin on here ?
I thought that you'd need some type of measuring equipment to do a compression check ?
yeah it's a pressure gauge, thats about it.

you stick it in the spark plug hole and you crank the engine...this measures how much compression you are making in each cylinder.
Old Jul 5, 2007 | 04:42 PM
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Ah cool.
Thanks for that 8)
Old Jul 5, 2007 | 04:47 PM
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Pull the fuel injection relay and crank away.
Old Jul 5, 2007 | 04:54 PM
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Originally Posted by Uncle Arthur
unplug the cas
Correct.
Old Jul 5, 2007 | 04:55 PM
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Originally Posted by jayc72
Pull the fuel injection relay and crank away.
Incorrect. Not with a wasted spark ignition system unless you ground the plug wire you removed. If you don't you have 30,000volts that has to go somewhere and it can ark inside the coil internally and blow an ignitor.
Old Jul 5, 2007 | 05:09 PM
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pull fuel fuse and remove wires. good to go
Old Jul 8, 2007 | 10:32 PM
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Cool

Originally Posted by jayc72
Pull the fuel injection relay and crank away.
That's what I did and it worked fine for me!

Now I am tearing her down for a head rebuild
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