Weird Clicking Sound After Scratched Undercarriage

[Contained]

Hey all, I recently was pulling into a very steep driveway and as it leveled out I heard a loud scratch as my car came over it. I checked for leaks or any hanging material but found nothing, I ran a check on the computer and it's saying that all systems are OK, and all of my gauges are reading normally.

The part that worries me is that whenever I am driving, under acceleration there is no abnormal sound, but as I am slowing down (either cruising or on the breaks) there is this weird clicking/grinding sound. I am at a loss as to what is causing it as I see no structural damage, but the sound is loud enough to be very worrisome, and tends to get louder the longer I drive.

I have only tried to drive it 2 times since, once to get home and once to see if it was still making the sound. If anybody has any idea as to what it may be or certain things to check it would be greatly appreciated as I don't want to take it into the shop unless I have to.

Thanks in advance,
Noah

[kaz02a4]

Is it repeatable every time you're slowing down, either on or off the brakes? And nothing like this sound has happened before you went over the driveway?

[Contained]

Yeah it's consistant any time I'm moving foreword and off of the accelerator (on or off brakes) and was never there before going over the driveway.

[seco007]

Does it sound like gravel? like "rocks" under your tires??? might be bearings... some one else (other than myself) had this same issue here........

what does the "sound" sound like...???

[AJacksA4]

I get a scraping sound on deceleration, when the revs are above 2500. No brakes, just coasting. Goes away the instant i touch the throttle, but its always there. TIP btw.

Not sure what it is, only time will tell i guess.

[Contained]

Thanks for the help, it does sound kind of like a scraping/ gravel in the tires, but it isn't a constant sound, its intermittent like t-t-t-t-t-t-t (where t is the scraping sound). I'll try to capture the sound tomorrow and upload it.
AJacksA4, how long has the sound been happening to you? and did you happen to scrape your underbody or did it just appear one day?

Do y'all think that it's okay for close to home neighborhood driving or could that worsen the problem?

[Contained]

And I'm TIP as well

[Solarsuplex]

I hit the bottom of my car on stuff all the time and never have experienced what you are talking about. Check all fender liners, plastic undercarrage. When up to speed the wind my bring the plastic stuff down and cause it to drag. Check the metal brace that is in the middle of the car going widthways that is under the exhaust. May be loose.

Maybe the mudflap things. I cant imagine anything going mechanically wrong after you scrape the bottom of the car..

[Contained]

Solarsuplex, thanks for the help. It was a kind of hard hit, less of a drag/scrape. I don't think anything is dragging as the sound is gone when i'm accelerating up and only comes back when i am decelerating (either on or off the brakes) I'll check the metal brace as that is (subjectively) where the "sound" sounds like it's coming from.

[Solarsuplex]

Otherwise only thing I can think of is a metal bracket somewhere along the exhaust that might have gotten loose an is rattling but that doesn't seem too likely.

[J.Owen]

Check the plastic under tray. It is two parts with a bracket in the middle of the two panels. Make sure its completely bolted on. I had one of the bolts come loose and while driving, air would get under the panel and pull it to the ground. It would skip along the road surface making a scratch ... scratch ... scratch noise.

[Contained]

I'm not sure exactly why but the sound is happening much less frequently and is much quieter when it's there. I'm going to take it in within the next few days to have it checked out just in case.

[kaz02a4]

If you can, see if you can put it up on a lift to get a really good look at it. Glad to hear it's going away though.

[audisline08]

Do I hear a skid plate in your future? Hope you figure it out! GL

[BenMTL]

Yah, just lift it and look for anything broken/out of place.

[Harddrive]

Contained, did you eventually find out the fault? I think I might have the answer you seek cos the same thing happened to my B5 three years back.

[Contained]

The sound is almost completely gone, now it's just barely audible when braking and doesn't happen every time. I never did find out what the problem was, but am taking my car into the shop anyway soon since I'm about to be on the road for a few months and don't want anything sneaking up on me. I'll update if they find anything.

Also, audisline08, a skid plate is my next vehicular investment.

Thank you all for your help.