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Misfire Problem

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Old 08-07-2006, 09:52 AM
  #21  
cooter69
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it sounds like a broken piston skirt or exhaust leak . if it was a valve out of adjustment the ticking would still be present.when the plug wire was taken off. if this engine has forged pistons that would be my first place to look
Old 08-07-2006, 10:16 AM
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73StreetRace
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You shoul dalso try to test the continuity of your spark wire with an ohm-meter. A broken wire can sometimes cause misfires...
Old 08-07-2006, 10:25 AM
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zwede
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My bet is on an exhaust leak. What did you use when you installed your header gaskets? I've found that unless I smear black RTV on both sides of the gasket they will blow out. Also, the gasket will compress after a few days of driving and if you don't retighten the header bolts the gasket blows out.
Old 08-07-2006, 10:25 AM
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Sorry ! It seems that you already tried this !
You can try to use a stroboscopic light on cylinder #5 and look
at the damper. Try it at different steady engine RPM. If the damper
appears erratic with the strobe light on it : you can be sure it is really
a misfire, and certainly ignition related...
Old 08-07-2006, 11:52 AM
  #25  
...Roger...
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Originally Posted by dwncchs
If you want to get rid of the tick and removing #5 does that -just leave the wire off !!!!! Sorry couldnt resist.Justin did you get the backfire problem fixed?-------- http://forums.corvetteforum.com/show....php?t=1410195
Justin if you still have that backfire problem it could be related to #5-Have you been to a shop in your area.In this previuos thread you have had a ton of advice-have you gone back and followed that advice?Everything cant be "OK" or the engine would be running right.You had to have missed something !!!--Maybe if other members would go back and look they could find something "WE" missed.
Old 08-07-2006, 12:59 PM
  #26  
JustinD
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Well, it ran fine for a couple drives. Then I let it sit for a week, came back and I had the misfire. I will have to check the exhaust gasket.
Old 08-07-2006, 01:40 PM
  #27  
...Roger...
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Originally Posted by JustinD
Well, it ran fine for a couple drives. Then I let it sit for a week, came back and I had the misfire. I will have to check the exhaust gasket.
So the backfire through the carb when you goose it from idle is gone ?The one we heard on the video.
Old 08-07-2006, 01:54 PM
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JustinD
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It was for a while, I don't know if it is there right now. I don't want to hammer it with that noise around.

Last edited by JustinD; 08-07-2006 at 01:59 PM.
Old 08-07-2006, 02:16 PM
  #29  
JustinD
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Ok, well I pulled the spark plug wires apart and tightened down the header. The ticking noise seems to be gone. Now I just need to get it set just right so it runs like a champ. Also I hit it down to the floor and it seems that the backfire is not there either. It is all coming together very slooooowly.
Old 08-07-2006, 02:39 PM
  #30  
Little Mouse
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Justin did you use studs in the heads for your headers??
Old 08-07-2006, 02:56 PM
  #31  
JustinD
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What studs? I used header bolts.
Old 08-07-2006, 03:25 PM
  #32  
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If you have aluminum heads replace the bolts with studs and 12 point
nuts and use anti seize on the threads.
Old 08-07-2006, 03:48 PM
  #33  
JustinD
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What will that do for me?
Old 08-07-2006, 04:30 PM
  #34  
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I just had it out and the backfire is still there. I think it is a tuning issue now. I need to get the timing dialed in just right and have someone do my carb. when I got home and shut it off it dieseled a bit.

Last edited by JustinD; 08-07-2006 at 04:36 PM.



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