8qtip5 Posted January 16, 2009 Share Posted January 16, 2009 Hi gents, I was wondering if any of you could help me with this issue. I just recently did a compression test on my Supra and was getting 168-170 on cylinders 1-4. However, when I went to test cyl #5, the starter was making a "huffing" sound (like it was somewhat having a hardtime) every few revolutions. It wasn't making that sound earlier when I tested 1-4. When I heard that, I looked at the gauge and got 90psi. I redid it again and got 60psi, and then finally got 30psi on that same cylinder in final attempt. I thought it was a weak battery causing it, so I jumped the battery for about 10mins and redid the test. I got the same 30 psi again on #5 and same huffing noise too. So I then figured it could be a bad tester and retested cylinder #4 (got 170psi earlier) and got 155psi now, again with that "huffing" noise. I have no idea what's going on. Any pointers? btw before testing, I just started the car and let it sit for about 20mins. Any help would be appreciated. Thanks Quote Link to comment Share on other sites More sharing options...
absz Posted January 16, 2009 Share Posted January 16, 2009 you should be testing the compression with all plugs removed and also disable the fuel injectors (relay) make sure battery is fully charged . Quote Link to comment Share on other sites More sharing options...
8qtip5 Posted January 16, 2009 Author Share Posted January 16, 2009 you should be testing the compression with all plugs removed and also disable the fuel injectors (relay) make sure battery is fully charged . EFI fuses #1 and #2 were pulled for the test as well as all plugs. What would the "huffing" sound be? Quote Link to comment Share on other sites More sharing options...
Tricky-Ricky Posted January 16, 2009 Share Posted January 16, 2009 Start with a fully charged battery, wedge throttle fully open, and test each cylinder by turning over the engine until the gauge doesn't rise any more, must be a proper peak hold or you're wasting your time. Quote Link to comment Share on other sites More sharing options...
SimonB Posted January 16, 2009 Share Posted January 16, 2009 Sounds like you may not have had the thing screwed in fully so it's leaking. Or the rubber O ring on it is dodgy. Quote Link to comment Share on other sites More sharing options...
Guest rossymond Posted January 16, 2009 Share Posted January 16, 2009 Sounds like either oring on the tester is foobed, or the valve on the side is leaking Quote Link to comment Share on other sites More sharing options...
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