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Engine cranks, but will not start

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  • #16
    Sorry for the delay, I was waiting for my friend to bring in his compression tester and he never did so I had to get it myself, but I finally got it tested. Results:
    Cylinder 1 ≈ 10 psi
    Cylinder 2 ≈ 60 psi
    Cylinder 3 ≈ 90 psi
    Cylinder 4 had no compression at all, the gauge did not move at all when I tested it. I am going to try a different coil in the next few days per william's advice. I tested the plugs again to see if they were getting spark myself and like he said, there was an orange tinge to the spark so I hope it will run, even if it runs rough after I put in a new coil.

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    • #17
      Ouch! Sorry dude, sounds like it's gonna take more than a coil :nightmare:

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      • #18
        Ouch, i think the minimum is 110 psi? I cant see that being the rings but did you put some oil in each cylinder and do a second test?
        When i checked my car last about 100k ago it was about 100, 95, 100, 115 i think. When i put a bit of oil in there they all went up to 225/250psi. That told me it was my rings. But zero psi? This is a non interference motor right? Any chance the camshaft is 180degrees off? Lol.
        Maybe the valves are so gummed up they aren't closing all the way? Or maybe your rings fell all the way off... Lol, i dunno. I would say it has to be the valves. But you see that hose that goes from the valve cover to the intake tubing? Take it off and plug your pcv hose. Then crank it over a bunch and stick your finger over the valve cover hole that you just took the hose off of. If theres lots of air there its the rings. If not probly easiest is to take the exhaust manifold off and see if the valves are seating.


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        • #19
          I can't believe an engine was running with those compression numbers. Maybe the lifters are not opening the valves all the way - or the airbox ate a plastic bag.
          When I'm good I'm very, very good and when I'm bad I'm HORRID.

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          • #20
            I can't believe an engine was running with those compression numbers. Like ryanprins says above^ could be valves not seating or maybe the lifters are not opening the valves all the way - or the airbox ate a plastic bag.
            When I'm good I'm very, very good and when I'm bad I'm HORRID.

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            • #21
              Better scenario: timing belt got loose and slipped a few teeth. Exhaust valves are staying open until just before tdc.
              You did say earlier you were going to check it but i dont see confirmation that you did.


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              • #22
                This was just with the engine cranking with the starter, something like ~ 250 rpm. This is not a running engine and I think there may be something else going on with cylinder 4 because when I pulled the spark plug there was no gap and it had a silvery tint to it. The PO said it had a valve problem but I was just going through the simple stuff before I started doing anything with the head. I need to test #4 again because I think I may have done something wrong with it.

                Also do you have to take any belts or accessories off to see the timing marks and pointer? I see where they are supposed to be on the bottom of the hood, but I can't find them.

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                • #23
                  Hmm, ya, sounds like more serious problems if the plug had a proper gap a couple days ago and none now...
                  Compression test is supposed to be done without the engine running. It will always get to the same compression numbers no matter how slowly it turns over, just takes longer when its slower. Maybe the compression tester wasnt threaded in tight enough? Can happen if the threads are a bit dirty.
                  Its printed on the hood? If thats not spark timing thats pretty handy.
                  Both upper and lower timing belt covers have to come off i believe. There is marks on the small crank pulley that the timing belt runs on and marks on the camshaft pulley that the timing belt runs on.


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                  • #24
                    When I got the car there was no gap, so I gapped it. And I can't do a test when it's running if it doesn't run, I just did it with the starter turning the engine so I could get relative numbers. The timing covers are both missing so that makes things a little easier for me, I was going to go to the junkyard and see if I could find some in decent condition today. And as far as what's printed on the hood, you should see a sticker when the hood is open that has a little vaccuum routing diagram and a diagram of the crank pulley and timing marks.

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                    • #25
                      Ok
                      Why would you want to try to test it while its running?
                      Ok
                      My hood was painted and i have no stickers, thats why i didn't know.


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                      • #26
                        Your compression is probably valves have cracked or chipped my nephews festy didn't run when we got it a compression test showed 30,15,0,0
                        It would run but only with out the belt. And to the floor was maybe 2500 rpms. I guess it wouldn't run with the belts because it was dragging the motor down to much. We pulled the head and found 4 bad exhaust valves the ones with 0 compression had holes in the valves and the 30 and 15 had cracks. .
                        The guy calmed the fuel pump was going out and finally just died he replaced the pump and it still wouldn't run so he sold it .
                        Best I can figure is it was running so lean with the bad pump it burnt the valves?
                        Last edited by william; 08-18-2015, 12:00 PM.

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                        • #27
                          I'm going to pick up a head today from the junkyard, hopefully it will be okayish when I pull it. If the valves are burnt I'll just get some exhaust valves from RockAuto and replace the one's on the head I have.

                          Sent from my LG-VS985 using Tapatalk

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                          • #28
                            A piece of valve must have hit the plug electrode.
                            When I'm good I'm very, very good and when I'm bad I'm HORRID.

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                            • #29
                              Update: I did not pull a head today for 2 reasons:
                              1) I did not have a 12 point socket
                              2) I figured it would be better to pull my head first to confirm that it is in fact bad valves. I will try to pull it tomorrow, but I will see what happens.

                              Sent from my LG-VS985 using Tapatalk

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                              • #30
                                Okay, I pulled the head on my car and I did not like what I saw, piston 4 had a chunk missing out of it and I could see one of the rings and the head did not look too good for that cylinder either. In cylinder 2 I found some metal shavings and the rest of the engine looked good. I'll probably pull the engine with a few friends eventually and just tear it down but right now it looks like it will be seeing a junkyard in the near future.

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