first start up with headers, loud banging?
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Well I got everything back on (finally) and when I started it up I heard a loud banging from underneath the car that would happen every few seconds, and when it happened, the engine seemed to loose rpms for a second and then come back up. What could this be?
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Sounds like a clearance issue. Many times your heat shields are so close to the headers that you have to slightly bend them until you get the needed clearance. Also check your motor mounts, they could be getting weak and causing more movement along with the larger diameter exhaust which is causing the banging. Worth a try and it's free...
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Alright those sound like what it could be. I tried driving it around and it got worse. Now it sounds like its backfiring...which I hear could be bad plugs or spark wires... Could an exhaust leak due to a part not being installed right also cause backfiring like that?
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like stated, normally it will be a Kmember or transmission mount/crossbrace. Also like stated its thinking its knock (must be damn loud!)
Car sounding like its backfiring doesnt seem related. Like stated...burnt plug wire, or some plug wires got crossed?
I would start it up, and get under it looking for the areas the loud bangs are comming from. You may need to reposition the y pipe. Would also double check that the plug wires arnt crossed and look for a burned one.
Car sounding like its backfiring doesnt seem related. Like stated...burnt plug wire, or some plug wires got crossed?
I would start it up, and get under it looking for the areas the loud bangs are comming from. You may need to reposition the y pipe. Would also double check that the plug wires arnt crossed and look for a burned one.
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Alright, I'll check the wires and plugs this week as well as where its banging. The banging went away for awhile, but then came back, so its confusing..
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Alright I"m pretty sure the banging is actually a backfire. I'm thinking the backfire could be causing the exhaust to hit something when it happens. I'm going to check my wires and plugs and hope that's the problem. It sounds like a shotgun going off actually. And it doesn't happen consistently really. It will backfire and then a few seconds later it will, then again, and then it might be like ten seconds before it doesn't again. So at times it seems like a sequence, but then it stops and then comes back. If the plugs and wires don't fix it I'll take a vid of it and post it and see what you guys think.
Sorry for the story there, just trying to describe it the best I could.
Sorry for the story there, just trying to describe it the best I could.
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To add to that, I've ruled out bad motor mounts for now (even though I will be replacing them) because I highly doubt that a sound this loud is caused by the headers hitting something. I am not getting an SES light either. Like I said, its like a shot gun going off which to me sounds like it would be a misfire, but I want to hear what you guys who have probably dealt with this before have to say.
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***UPDATE***
I found out that one of my spark plugs was very loose, I could move it with my fingers. Also it appears that the little silver part of the plugs that plug into the wire (the very end of it) are threaded and a few of them were loose. Could this really be an issue? What do you guys think? Bare with me here lol
I found out that one of my spark plugs was very loose, I could move it with my fingers. Also it appears that the little silver part of the plugs that plug into the wire (the very end of it) are threaded and a few of them were loose. Could this really be an issue? What do you guys think? Bare with me here lol
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Alright, I tightened the spark plugs and what not, its still banging. Now I think that maybe it really is something loose that is just hitting the car somewhere. Now I just need to find out where its touching.
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get a video of what you are describing maybe that could help...
also try doing it at a stop, in neutral if it doesnt bang when you stomp the gas and does when in gear... its probably a mount, trans or engine... or even exhaust hitting somewhere.
also try doing it at a stop, in neutral if it doesnt bang when you stomp the gas and does when in gear... its probably a mount, trans or engine... or even exhaust hitting somewhere.