Weird Vibrating / Loose part sound under ACCEL

**ss~zoso~ss** · 07-13-2007, 06:57 PM

I installed headers recently about 2 months ago, and a while back some time after the install, a vibrating sensation would come from the rear of the car under hard accel ( not necessarly WOT)

last night I did a burnout (rolling 5mph clutch dump) and it really sounded like something was loose and bouncing around ( not wheel hop)

when i am driving normally there is no vibrating or anything but under the hard accel this is when it happens

when i got home i checked my aftermarket panhard bar to see if it was loose but it didnt seem it, gave the sway bar a tug and that didnt seem loose,

do u guys have any suggestions as to what this could be?

any help is greatly appreciated,

Jeff

**Zapper2003** · 07-13-2007, 07:30 PM

Maybe not necessarily of any help, but on my 97 hardtop bird, i have issues on occasion that sounds just like yours. quick rundown: stock manifolds, stock cats, stock intermediate pipe, and dynomax muffler in the stock place. however, under some cornering and on occasion hard launching (such as from roll or standstill in a parkinglot etc) i have a crazy loud metal on metal vibration/rattle. The best I can figure out from looking is that my I-pipe is touching the trans crossmember (or some other crossmember under the car, i cant remember for sure) under certain torque/twisting situations. Its annoying and embarassing because its loud in the car, i can only imagine what its like outside of the car. The first night i heard it i thought i lost a heat shield or something, it sounded as if it were grinding on the driveshaft, however i was going through a hard corner at the time with some speed on, and it went away and came back again after that hard launch and some other corners. Good luck!

**ss~zoso~ss** · 07-14-2007, 11:42 AM

na i dont think my noise has anything to do with my exhaust

MORE HELP PLEASE!!!!

**secondgearscratch** · 07-14-2007, 11:44 AM

nothing looks like it rubs on the phb or anywhere ?

nothing is hitting the rear axle??

**ss~zoso~ss** · 07-14-2007, 12:16 PM

yea something is hitting the rear end, on the back of the PUMPKIN/MEATBALL there are some marks, i assume from the rear sway bar?

could this be the culprit, should i just get a new one with all the bushings?

**ss~zoso~ss** · 07-14-2007, 01:11 PM

should there be that much play in the rear that the sway bar would scrape up against the differential?

**Zapper2003** · 07-14-2007, 06:50 PM

do you have stock LCA's? Maybe the bushings are worn enough to allow the rearend to move back enough to contact it under acceleration (which also causes the car to squat furthering the interference)

**ss~zoso~ss** · 07-14-2007, 07:31 PM

yea they're stock but i'm not sure if thats the case, i'm leaning towards the sway bar because of the marks i found on the back of the differential

**0rion** · 07-14-2007, 09:32 PM

LCA's will usually "pop". Is it 100% from the back of the car? My initial thought was tranny mount but my understanding of your description is that it's further back than that. What do your sway bar brackets look like? The sway bar should be bolted to the rear with U-bolts. I would have to think on this one as to what would cause it to hit the pumpkin. I guess maybe if your bushings were completely shot it might???

**ss~zoso~ss** · 07-15-2007, 01:43 PM

yea its attached with u bolts, but thats the only thing that could hit the diff in that area where the marks were, so i'm now thinking about maybe getting a performance rear sway bar