mra32 Posted July 16, 2010 Report Share Posted July 16, 2010 (edited) http://s318.photobucket.com/albums/mm432/dieslowlymf/W-Body%20Meet/?action=view¤t=SAM_0693.mp4 Maybe the valves are messed? Maybe its a closed loop kind of thing. Lifters stuck open, causing the cylinder to not be sealed when the valves expand? Edited November 13, 2010 by mra32 Quote Link to comment Share on other sites More sharing options...
mra32 Posted July 17, 2010 Author Report Share Posted July 17, 2010 B-MUP Quote Link to comment Share on other sites More sharing options...
tornado_735 Posted July 17, 2010 Report Share Posted July 17, 2010 On the second dollar bill test, was it sucking the dollar in more often than the first time you did it? Quote Link to comment Share on other sites More sharing options...
AL Posted July 17, 2010 Report Share Posted July 17, 2010 Yah cause the video doesnt show it as you set the camera down lol Quote Link to comment Share on other sites More sharing options...
RobertISaar Posted July 17, 2010 Report Share Posted July 17, 2010 photobucket video is FTL... i sat there 5 minutes waiting for it to buffer and i got all of 10 seconds of video. Quote Link to comment Share on other sites More sharing options...
mra32 Posted July 17, 2010 Author Report Share Posted July 17, 2010 dag yo.. sry br0z. For the dollar bill test, First it was like once every 10 seconds or so. When i go back to the exhaust for the second time, you can hear it change quite abruptly, if you turn your sound up. This is when I do the second dollar bill test and yes, its like wayyy more frequent, like 2 or 3 per second. Quote Link to comment Share on other sites More sharing options...
xtremerevolution Posted July 17, 2010 Report Share Posted July 17, 2010 (edited) This is the same thing that happened to the Regal. In my case, it was a burned valve, as replacing the heads solved the problem. Time to look for a new set of heads. Have a look through this thread while you're at it: http://www.w-body.com/showthread.php/44906-Fixing-my-burned-valve...?highlight=burned+valve Check out my video. Let me know if it sounds similar in regard to that puttering sound. Edited July 17, 2010 by xtremerevolution Quote Link to comment Share on other sites More sharing options...
mra32 Posted July 17, 2010 Author Report Share Posted July 17, 2010 yes it sounds the same...im not doing heads on this...its a a dog of a V6 thats not worth having any work or money thrown into and the gaskets alone cost like $100. What gets me is the bigass difference from when you just start it up to when it gets warm. I dont know what the explaination could be...probably valvetrain related though. Quote Link to comment Share on other sites More sharing options...
xtremerevolution Posted July 17, 2010 Report Share Posted July 17, 2010 yes it sounds the same...im not doing heads on this...its a a dog of a V6 thats not worth having any work or money thrown into and the gaskets alone cost like $100. What gets me is the bigass difference from when you just start it up to when it gets warm. I dont know what the explaination could be...probably valvetrain related though. You know, it could also be a lifter stuck open as you mentioned, or even a broken valve spring. Only way to really tell is to get the valve covers off and get a compression test done. If a compression test shows low on one of the cylinders, then you'll know one of your exhaust valves isn't sealing properly. Quote Link to comment Share on other sites More sharing options...
mra32 Posted July 17, 2010 Author Report Share Posted July 17, 2010 what size (diameter) spark plugs are these?...i have a compression tester with a few adapters. Cant really do a compression test without removing all the spark plugs though...dang. Those are a beotch on this car. Quote Link to comment Share on other sites More sharing options...
RobertISaar Posted July 17, 2010 Report Share Posted July 17, 2010 ..... 15mm? it's been a while. Quote Link to comment Share on other sites More sharing options...
xtremerevolution Posted July 17, 2010 Report Share Posted July 17, 2010 what size (diameter) spark plugs are these?...i have a compression tester with a few adapters. Cant really do a compression test without removing all the spark plugs though...dang. Those are a beotch on this car. Well yeah, that's the nature of a compression test, haha. I did mine one at a time. I disconnected the fuel injectors and removed one spark plug at a time. Quote Link to comment Share on other sites More sharing options...
mra32 Posted July 17, 2010 Author Report Share Posted July 17, 2010 Might this kind of BS be caused by a vacuum leak? I should replace my upper intake gaskets... Quote Link to comment Share on other sites More sharing options...
xtremerevolution Posted July 17, 2010 Report Share Posted July 17, 2010 Might this kind of BS be caused by a vacuum leak? I should replace my upper intake gaskets... Can't see how an intake vacuum leak can cause exhaust negative pressure, unless your EGR is spazzing and allowing pressure to be sucked right through at idle. Quote Link to comment Share on other sites More sharing options...
Crazy K Posted July 17, 2010 Report Share Posted July 17, 2010 I do not think it is a valve, because it would be consistently missing. It could be a weak valve spring, it could be a sensor gremlin... do a compression test. P.S. I noticed an odd misfire sometimes at lower idle in my long gone 92. it was due to a half bad injector. HAVE YOU OHM CHECKED YOUR INJECTORS? Quote Link to comment Share on other sites More sharing options...
xtremerevolution Posted July 17, 2010 Report Share Posted July 17, 2010 I do not think it is a valve, because it would be consistently missing. It could be a weak valve spring, it could be a sensor gremlin... do a compression test. P.S. I noticed an odd misfire sometimes at lower idle in my long gone 92. it was due to a half bad injector. HAVE YOU OHM CHECKED YOUR INJECTORS? Ken, with all due respect, please describe any other cause in a a car that will produce *negative* exhaust pressure. Quote Link to comment Share on other sites More sharing options...
GutlessSupreme Posted July 17, 2010 Report Share Posted July 17, 2010 (edited) Actually EGR valve might be a good point, since that doesn't start operating until closed loop. Otherwise, I'd definitely say a valve isn't sealing correctly, at least not when it should be. edit: no maybe that doesn't make sense, because that's how EGR's operate normally anyway.. Edited July 17, 2010 by GutlessSupreme Quote Link to comment Share on other sites More sharing options...
spiderw31 Posted July 17, 2010 Report Share Posted July 17, 2010 Could be a burned valve, what with the negative exhaust pressure and all. Really odd though, as it really shouldn't change suddenly as it goes into closed loop like that. If a valve is burned, it is burned. It shouldn't change going in and out of closed loop. I agree the best start is a compression and leakdown test, as that should be definitive.. Quote Link to comment Share on other sites More sharing options...
mra32 Posted July 18, 2010 Author Report Share Posted July 18, 2010 Well im pretty sure I had a leak on the intake manifold. I'll be getting some gaskets to fix that tomorrow morning and see if that clears up the ridiculous running issue. Kinda funny when you have to ride your motorcycle to get car parts. I'm ok with the occasional "bump" in the exhaust note, so if thats all i have when im finished with the intake, i'll be happy. I also get to replace my somewhat crappy PCV valve with the one I purchased for it 5 or 6 years ago with a new non-plasticy pcv hose. Hooray! Quote Link to comment Share on other sites More sharing options...
Crazy K Posted July 18, 2010 Report Share Posted July 18, 2010 Ken, with all due respect, please describe any other cause in a a car that will produce *negative* exhaust pressure. I can't but the following states what i agree on: Could be a burned valve, what with the negative exhaust pressure and all. Really odd though, as it really shouldn't change suddenly as it goes into closed loop like that. If a valve is burned, it is burned. It shouldn't change going in and out of closed loop. I am going to ask this simple question: would a misfire result in negative exhaust pressure? Quote Link to comment Share on other sites More sharing options...
BXX Posted July 18, 2010 Report Share Posted July 18, 2010 Would a miss create tthe 'negative' exhaust pressure, absolutely as the miss fucks up exhaustt scavanging and disrupts flow. Quote Link to comment Share on other sites More sharing options...
xtremerevolution Posted July 18, 2010 Report Share Posted July 18, 2010 Would a miss create tthe 'negative' exhaust pressure, absolutely as the miss fucks up exhaustt scavanging and disrupts flow. Yes, so that should merely stop the exhaust from flowing, not reverse its flow back into the car. If a cylinder isn't firing, on the exhaust stroke, it will put out as much as it took in on the intake stroke. Quote Link to comment Share on other sites More sharing options...
Crazy K Posted July 18, 2010 Report Share Posted July 18, 2010 I'm going to unhook an injector and do this test myself for the answer. Quote Link to comment Share on other sites More sharing options...
Night Fury Posted July 18, 2010 Report Share Posted July 18, 2010 Ken to the rescue! Make sure it doesn't have a burned valve to begin with!! Lol Quote Link to comment Share on other sites More sharing options...
xtremerevolution Posted July 18, 2010 Report Share Posted July 18, 2010 All this speculation could be put to rest with a compression test. Quote Link to comment Share on other sites More sharing options...
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