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Want to do Compression check

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Old 07-01-2007 | 03:15 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 07-01-2007 | 06:46 PM
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What I would do is pull the two harnesses off of the CAS.
Old 07-01-2007 | 06:48 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 07-01-2007 | 11:17 PM
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I just pull the wires for the injector harness and coils.
Old 07-02-2007 | 10:25 AM
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unplug the cas
Old 07-04-2007 | 10:00 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 07-04-2007 | 11:07 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 07-04-2007 | 11:24 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 07-05-2007 | 05:42 PM
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Ah cool.
Thanks for that 8)
Old 07-05-2007 | 05:47 PM
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Pull the fuel injection relay and crank away.
Old 07-05-2007 | 05:54 PM
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Originally Posted by Uncle Arthur
unplug the cas
Correct.
Old 07-05-2007 | 05:55 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 07-05-2007 | 06:09 PM
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pull fuel fuse and remove wires. good to go
Old 07-08-2007 | 11:32 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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