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What is this noise........

2K views 15 replies 9 participants last post by  ClarkWGriswald1 
#1 ·
I need some help guys. In the past few days my car has developed a very strange noise. Before I explain the noise, let me explain the conditions when it happens. The noise only happens when the car is in reverse with the brakes applied. Once the brake is released and the car starts moving, the noise goes away. If I keep my foot on the brake and switch out of reverse, the noise goes away. Also, the noise only happens on cold starts. After the car warms up, the noise can not be duplicated even if in reverse with the brakes applied. The noise also seems to be worse the colder the temp is outside.

The noise seems to be a vibration type noise that sounds god awful. It rattles the whole cabin. The noise also seems to be coming from the drive line somewhere. To me.....it sounds like its coming from the transmission but the way its viibrating, it might not be.

I made a quick video. Ignore my hands and everything all over the place. Listen from like 50 seconds on. Like always, the video doesnt sound nearly as bad as it does in real life.

http://youtu.be/AIixcY_ZiMc

Suggestions? Torque Converter? Trans?
 
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#2 ·
Anybody?
 
#5 ·
Negative. I'm taking the car to livernois Monday or Tuesday. I'm leaning towards it being exhaust related. Maybe something is lose?
 
#6 ·
Is your neighbor's cat missing?
 
#7 ·
Sub'd...
 
#10 ·
^^ What he said
 
#11 ·
I went to livernois today. I'm letting the car get cold......in about an hour I'll know if what they did fixed the issue. Stand by a little bit........
 
#12 ·
Well..............It appears to be fixed. Ill give it over night to get "cold" and check it again tomorrow but all is looking good at this point. (keep fingers crossed for tomorrow.)

First off: Kudos to Livernois. Once again, they were great. I told Andy about the issue, and he immediately said to bring it in and they'll take a look. I brought the car in today and within 5 minutes, it was up on the rack and being looked at.

The noise appears to have been caused by an exhaust issue. One of the bolts on the clamps was hitting the heat shield. The exhaust pipe itself was not touching, just the botl. Im not sure how the clamp moved....but oh well. When looking at the heat shield, it was pretty apparent that the bolt was hitting it. There were some pretty significant "witness marks" on the shield. Im still not sure why being in "reverse" and being cold made the noise appear. Maybe putting it in reverse and engaging some torque caused the motor/exhaust to shift a fraction of an inch.......making the bolt touch the heat shield?

I'll check it out agian tomorrow and hopefully she's fixed.
 
#13 ·
No noise this morning.............shes fixed.
 
#15 ·
i had a smilar issue turned out to be a stupid tree branch that some how made its way on top of the heatshield. lol

little thing that was maybe an inch long but made some crazy rattles when cold only.
 
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