Honda Bull

Okay. So what would cause one cylinder to be extremely high as opposed to the others... I'm looking at this USDM GSR motor and all of the cylinders were at 210 but one happened to jump extremely quickly to 270. Was it just improperly done? Or is there something wrong there?

Thanks, Shaun

t0p_sh0tta

Test again and see if you get similar results.

LSVTEC 91 Civic

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by HondaBullSQ &raquo;</TD></TR><TR><TD CLASS="quote">Okay. So what would cause one cylinder to be extremely high as opposed to the others... I'm looking at this USDM GSR motor and all of the cylinders were at 210 but one happened to jump extremely quickly to 270. Was it just improperly done? Or is there something wrong there?

Thanks, Shaun</TD></TR></TABLE>

Thats high for a GSR... I'd say do it again. Are you doing the test with the ECU fuse out, and holding the pedal at WOT?

maxspeedhonda

I am guessing that you did the test incorrectly. Try again.

Honda Bull

well.. the car was a wrecked 1995 GSR that the guy bought and he's selling me the whole swap for cheap. All it'll need is the passenger axle (it got pulled out of the boot upon impact). He never received the key for it so he had to do the test without directly using the ignition inside the car (not sure how it's actually hooked up to do this).

He had said it registered 200 across each cylinder before I had gotten there. He's a trustworthy guy so I'm not worried about it. Wasn't sure if there was something that would cause the cylinder to jump like that.

PyroProblem

valve adjustment out of spec for that cylinder...

bonestockls

I don't see misadjusted valves would do anything but bring numbers down for that particular cylinder. A cylinder with carbon build up would definitely spike compression numbers. Perhaps the valve seal or guide on that cylinder allowed oil to be pulled into that cylinder or that cylinder was suffering from incomplete combustion/missfiring , etc.

CovertFI

That cylinder could have a lof of carbon build up.

Honda Bull

Like all I could think of would be that the carbon did build up. I didn't think it would make the compression that high and/or make the compression tester rise so quickly. I think the motor might be out of the car right now so how hard is it to do a compression test then???

LudeyKrus

If it's sat for a while, water or oil could have seeped into the cylinder and displaced the air, causing the compression #'s to be much higher.

Pull the plugs and turn it over to see if it clears out any oil or water.