Rep Power: 0

ok so i got a brand new magnaflow exhaust put in 2 weeks ago...first off the place i took it basicly f'd me over cuz they charged 150 but said i would have 2 come back because they could finishbecause of a rusty bolt and would charge an extra 150..forget that!! so i took it 2 an auto shop who not only charged less but did a better job mounting it for half da price....but this is the problem the exhaust seems to make a rattling or knocking sound every so often..which only i can hear inside..it gets pretty annoying..the mechanic told me it was because the exhaust fits lose..so all i wanna know is what exactly is it and is there anything i can do 2 fix it.

 
Rep Power: 237

exhaust is probably knocking on the swaybar mount/suspension arm, etc.. under the car. Where the work was performed.

get under the car best you can, grab the exhaust and start tugging it around. itll hit something im sure while your heads under there.

 
Rep Power: 221

I have the same system, and the same problem. Does it vibrate the entire car when you're driving? Mine seems to be rattling against the floor. But...ONLY when it's raining heavily (i.e. water splashing up against the exhaust system).

 
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mine rattles against the floor 2 mainly right under me, but it doe it also wen its nice out but not as much

 
Rep Power: 230

+mm+ i can tell you exactly what the problem is.

when i first installed my tsudo catback system, it made that same rattle and vibrate which seems to be coming from under you, but its actually coming from under the front passenger seat. and yes, if it snows and water gets up there, or if it rains, it gets louder rattles more. i had that exact problem as well.

basically, your catback system comes in multiple pieces that bolt together at the flanges. directly under the passenger seat, there is a heat shield. it is a piece of sheet metal plating that is there to prevent heat coming up from the exhaust into the area of the passenger seat. i will bet that two of the pieces of your catback system bolt together directly underneath that heat shield just like mine. when your car is on, your exhaust is always moving, and its sitting so close to that heat shield, that it taps against it. when theres more weight in the car, the noise is even a slight bit worse. what you need to do is get under the car with a pair of tin snips, and notch out just the sides of the heat shield on both sides, right above where the flanges of your pipes come together. since your heat shield is slighting curved, you dont need to take it out or make a mess of cutting it. just make a cut in the shape of a wedge on the outside, and the inside edges of the heat shield so that neither side touch the flanges.

this sounds exactly like +mm+'s problem and maybe even geo's. you guys should get under there and try to snip a couple little pieces off. it took me maybe 3 minutes in total.

 
Rep Power: 0

this happened to mine too, i took it to an exhaust shop and the heated it up and lossened the tension and itstopped, the other thing peoplehave said is that to which the sway bar to an ex (si) if it's an dx/lx

 
Rep Power: 221

^ unTuned...

Interesting. I had my system welded together due to the clearance of the U-clamp bolts. It definitely does not sound like metal-against-metal. It is a deep-toned 'thudding' sound. Anyway, I'll have to check it out.