Exhaust Rattle Help!!
#1
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Ok, so I just installed jba catless mids on my car a few weeks ago. I have stock manifolds, jba catless mids, and a magnaflow catback. I noticed a rattle that happens only when engine is under load decelerating. It sounds like it is from the middle section of the car, and happens like around 1400-1200 rpms on decel while driving. It's really annoying and sounds like crap. So I threw it up on the lift everything is perfectly tight. I replaced my exhaust hangers in the rear, and there is no slop. Where is this noise coming from????
#2
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that rattleing is probably rasp, not an actual rattle. i had and have the same issue when i replaced my catted mids with catless mids. i replaced my exhaust which was a jba catback with a bassani that comes with a perforated x pipe and it cut down on it alot. bviously without actually hearing it this is all a guess but it could be the issue. if you are interested i have a pair of jba catted mids with 7,000miles on them for sale. pm if you want.
#3
Staging Lane
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I actually had the exact same problem. It happens at low rps when the engine is under a load (for me it was when the car would drop from 2k - 1k while in gear.) Not harmful or anything but it made the car look like a POS. And like you - i checked under it on a lift and nothing was loose. The guy I bought the car from said it was a heat shield over the cats but they were secure.
Anyway, installed the new headers and y-pipe and it went away. Also removed the cats. Not sure which of the previous fixed the problem, but one of them definitley did.
Anyway, installed the new headers and y-pipe and it went away. Also removed the cats. Not sure which of the previous fixed the problem, but one of them definitley did.
#4
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I actually had the exact same problem. It happens at low rps when the engine is under a load (for me it was when the car would drop from 2k - 1k while in gear.) Not harmful or anything but it made the car look like a POS. And like you - i checked under it on a lift and nothing was loose. The guy I bought the car from said it was a heat shield over the cats but they were secure.
Anyway, installed the new headers and y-pipe and it went away. Also removed the cats. Not sure which of the previous fixed the problem, but one of them definitley did.
Anyway, installed the new headers and y-pipe and it went away. Also removed the cats. Not sure which of the previous fixed the problem, but one of them definitley did.
Ya, mine happens at the same spot as yours did..I'm gonna buy the shorty headers and see if that solves the problem..it really drives me nuts..
#7
TECH Enthusiast
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When you say under the middle of the car, do you mean under the center console area? If so I had a similar problem, once again everything was tight, and it ended up being the bottom of the exhaust was hitting on the crossmember piece that runs under it. I took a piece of heater hose, slit it to make it flat, shoved it between the two and haven't had a problem since.
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#8
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Ya sounds like right under the center console, but i'm not a 100 percent sure...my thought was the little inserts that go into the mid pipes to connect to stock manis were bouncing around? But it's tight down there so i don't know..And no I don't live in cali, i just bought jba catless mids that connect to stock manifolds, and the only headers that connect to those are shorty's.. i would have to sell those and then buy lt's and catless again. so i figured i would buy shorty's, but everyones telling me lt's bc better power...
#9
Staging Lane
iTrader: (2)
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When you say under the middle of the car, do you mean under the center console area? If so I had a similar problem, once again everything was tight, and it ended up being the bottom of the exhaust was hitting on the crossmember piece that runs under it. I took a piece of heater hose, slit it to make it flat, shoved it between the two and haven't had a problem since.
And about the headers, if you can cope with the usually terrible ground clearance, LT's are the way to go. I had shorties on my other ls1 and it didnt have nearly as much sound or power gain compared with the LT's i have on this one.