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This Is My 3rd Forum Compression Test Question

HCR32INUSA

By HCR32INUSA,
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HCR32INUSA Newbie

HCR32INUSA

Posted
Posted (edited)

This question isn't critically important. I guess it's more of a way for me to find the best forum.

My question pertains to compression testing/leakdown testing of my r32 rb20 gtst. I searched everywhere on google and Bing and on forums and came across just a couple that mentioned the question I have. The spark and fuel need to be cut. But nowhere on the net that I could find tells me which fuse to pull or which wire to pull for spark. One set of directions state to remove the wire from the igniter but there are 3 wires leading into it. Then on another forum they say to jus lt unplug the cam angle sensor (can someone verify this cuts both spark and fuel and doesn't mess with any sort of timing). I never really worked on cars ever and I'm changing spark plugs coil harness and a faulty coil pack. I might as well do the compression and leak down while I'm here. I'm just new to this stuff and just need a more detailed set of directions before proceeding.

Edited by HCR32INUSA
Duncan Grand Master

Duncan

Posted
Posted

there are conflicting instructions because they both achieve the same thing; but like Adrian said, if the CAS is unplugged the ECU won't know the engine is turning, so it will not give either spark OR fuel

tridentt150v Grand Master

tridentt150v

Posted
Posted

doesn't mess with any sort of timing).

It doesn't mess with cam timing or affect the results you get from your compression test, but removing and replacing the CAS does affect your ignition timing. When you re install it you will have to use a timing light on it to get it back to the correct timing mark [15 degrees at 650 rpm for R33's, not sure about RB20's, but search cos somebody will know].

Ben C34 Grand Master

Ben C34

Posted
Posted

It doesn't mess with cam timing or affect the results you get from your compression test, but removing and replacing the CAS does affect your ignition timing. When you re install it you will have to use a timing light on it to get it back to the correct timing mark [15 degrees at 650 rpm for R33's, not sure about RB20's, but search cos somebody will know].

Which is why it's handy they put a plug on it so you just disconnect the plug and leave the cas in place.

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