backfires
#1
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i have a 95 camaro with 68k miles it sounds like it backfires through the exhaust at 4000 rpm when i stand on the pedal, but it does not if i ease into it, it will go to the rev limiter. its had a new fuel pump,egr replaced,and fuel filter. i was told the cat was clogged so i removed it. the car runs great other wise. from a dead stop it just bucks and kicks when reaching 4000rpm. it shows no codes at all
#2
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Kinda sounds like what my car does. I about 2K rpm in 1st gear, if I got straight from 15% throttle to 100% it backfires, it's weird. I would like to know what that is...
#4
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Check yer plug wires, mine is doing the same thing. It's awaiting new wires, if this cold *** weather will ever go away. Raise the hood at night and look for sparks flying, mine is so bad you can hear it inside the car sometimes, and it lights up pretty good.
#6
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If it idles smoothly, check for exhaust leaks around the headers (or exhaust manifolds). I've seen this a few times with loose y-pipes or missing donuts--especially above 4000rpm on LT1/LS1's.
#7
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Originally Posted by LTSpeed
If it idles smoothly, check for exhaust leaks around the headers (or exhaust manifolds). I've seen this a few times with loose y-pipes or missing donuts--especially above 4000rpm on LT1/LS1's.
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#9
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if wires dont do it for you, i say ICM. ignition control module. if the ICM starts to go bad, youll end up with weird problems like that. could cause hard starts, but typically causes backfires and rough engine problems when theres a load on the engine. free reving my not do much, but you try to go down the road and youll have problems. that type of thing. but like i said if you see arching on the number 7 start with that. replace it and check your plugs too while your there. the ICM is on the drivers side cylinder head right above the coil. has the three plug connector going to it. takes a 5.5mm socket to get the two small bolts holding it on out.
#11
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Originally Posted by Snow Dog
the ICM is on the drivers side cylinder head right above the coil. has the three plug connector going to it. takes a 5.5mm socket to get the two small bolts holding it on out.
here it is
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Checked yer header bolts? They tend to come loose from time to time. Look at all the exhaust joints/connections, if there is alot of black soot around the connection then there is a leak. Feel around every joint for exhaust gas blowing out, be careful, don't burn yerself. You could take it to a muffler shop and put it on a lift, that would make it alot easier to find it.
#15
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Sorry for not getting back to this more quickly. The only areas you need to look for exhaust leaks are ahead of the O2 sensors. Anything after that will have no effect. The most common area is the donuts at the end of the exhaust manifolds. On cars with headers, there could be a number of areas, like next to the heads, or around the collectors, depending on the design and quality of install.
Look for black "soot" or burn marks. Also, you might hear something that sounds more like a ticking sound than a leak. Be careful if you try to find it with your bare hand--it could burn you.
Look for black "soot" or burn marks. Also, you might hear something that sounds more like a ticking sound than a leak. Be careful if you try to find it with your bare hand--it could burn you.