Really bad rattle, possibly in gas tank?

Ok, here's the problem: Ever since I had my new 3" turbo-back exhaust installed I've had a really bad rattle both inside and out of my car. It really does it bad when letting off in first gear while going through a parking lot idling down. I took it back to the muffler shop and drove them around and they heard it also, but when they raised it up they couldn't find it. They even beat on the pipes and they aren't touching anywhere. I thought that maybe there was something hung up in my piping but can't see where it would. Well, this weekend while I was doing my springs I tried to find it again with a friend's help. It seemed to make the same sound when beating on the underside of the gas tank. We took the fuel pump out to observe but couldn't see anything for the baffles. Definitely still sounded like something in the tank even when the pump was out. Anyone else with the same problem? Anyone have any ideas what this could be or what I can do to fix it? Any info. is appreciated. Thanks.

i bet you its your heat shields rattling
there is one above the muffler, and one where the cat used to be, they are bolted in and hard to get off. Both of mine rattle, the rear one worse than the middle. It was so bad that it would vibrate up through the car and off the rear panel , i eventually stuffed cloth up between the shield and the car, it works, but im gonna see if i can get them off when i put on the ION exhaust.Have someone stand near the muffler and rev the engine, mine would inly go at a certain rpm range, it was annoying as hell.

I had a customer with a similar complaint with stock exhaust. I also came to the same conclusion, the gas tanks have a lot of baffling in them and it sounded like one was coming loose. I ordered a gas tank, when it came in I found the new one to make the same noise the old one did. After that I banged on my own gas tank and found to make the same noise also. The only thing I can say is the stock gas tanks make ALOT of noise, however it is considered normal....I would look somewhere else for the rattle. Perhaps the rear seatbelt, have seen a few of those rattle.

Thanks for the info. guys. It does only seem to happen at a certain rpm range and it is a metal on metal rattle. Also seems worse after the car has heated up some. I thought it maybe the heatshield on the bottom off the gas tank or something between it and the actual tank but I can't access it because the shield is riveted on. Is it possible to shove something between the heatshield and the tank? Any tips on what to use and how to put it in? Thanks again.

all i did was shuve a couple rag pieces in between the heat sheild and car and now its fine, but its starting to rattle after about 2 months like that so soon i will go back in and readjust or just remove the shields entirely(if possible)

Get those rags outta there - you want to start a fire? If it's possible, just clamp the heat shields down with muffler clamps or even stainless hose clamps, bnever rags. Rags absorb moisture (bad), absorb oil (worse), and once dried will catch fire, smoke, retain heat where you do not want it, etc. Not a good solution. Besides, on a stock exhaust, those things are all COVERED UNDER WARRANTY. Do it right.

Betcha the exhaust is expamding when it's hot and hitting something - take a good long drive (1/2 hour+) and leave the car on while looking under or jacking up and (carefully, with a gloved hand) wiggling the exhaust. Mine would expand over an inch in total length - probably more like 2 - and that can really change the relationship between the pipe and the undercarriage.

General rule - if a noise or abnormality crops up right after a mod, generally it's mod related.

Good luck!

you could also try to get the exhaust hangers from Kartboy and that should reduce the amount of movement by your exhaust... good luck and do get the rags off of your exhaust... (flame)

amen to kartboy hangers...work great

could be inside the muffler itself.....i hade a Airmass engine-back on my old car.......had a huge RATTLE.......and i absolutely could not find it.........until i unbolted the axle back, held it by the mounting hook and struck the tip with the heel of my hand....HUGE RATTLE THEN.......it was inside the can itself.....if your hearing a rattle and its rpm dependant its that or a heat shield



oh but the way the shop i ordered it from ordered a new one to replace the rattly one ....it did the same thing.....luckly i found out before i mounted it
(burn)
P.S. I had already removed every heat shield on the car.....I DO NOT RECOMMEND THIS.......if the car did not rattle before its the exhaust itself or the exhaust hitting something........my car was UNBAREABLELY HOT after removing the heat shields

i had the same problem with the rattling at certain RPMs. Turns out, the exhaust would rest on the axle and that was what was causing the rattling. I guess my new exhaust is heavier than the stock one. Got the rear Kartboy Hangers in, and the rattle is gone...

ping said:

Get those rags outta there - you want to start a fire? If it's possible, just clamp the heat shields down with muffler clamps or even stainless hose clamps, bnever rags. Rags absorb moisture (bad), absorb oil (worse), and once dried will catch fire, smoke, retain heat where you do not want it, etc. Not a good solution. Besides, on a stock exhaust, those things are all COVERED UNDER WARRANTY. Do it right.

Click to expand...

First off, i have an aftermarket exhaust on my car and getting the dealership to do any work on that area is impossible. I have gone to 4 or 5 different dealerships nd they all say the same thing.I also dont have time to drive around the state to find a dealership that will work on it. Everywhere I go they wont touch it, and i dont really have the resources nor the time to get into a legal battle over heatshelid rattle warranty work.

Secondly, i have checked and rechecked the area that i have the rag on. It is a spot that does not even get warm, let alone hot. I have tested it many times and its too far away from my muffler to get warm. Since i have a straight through exhaust(no cats) and canister, i dont really get the hotspots that occur with a normal system. Most of the heat just passes through to outside.

I appreciate your concern but i think your mental picture of my car was more drastic than what is actually going on. Its not like im riding around with eight rags hanging off the back end of my car. Just a small piece wedged between two metal parts that dont get warm. I wouldnt do it unless i was absolutely sure that there was no danger. It will just have to work until i can get in and somehow pry those rivets out.