14 captured repliesDiscussion pagination complete · Source accounts, not a confirmed diagnosis
THIS DISCUSSION / SOURCE-DERIVED OVERVIEW
Discussion summary
YOUR RESEARCHStrange Noise Under Car
Leading reported evidence
Run over a raccoon
Performed · outcome unconfirmed
No successful repair reported for this finding.
0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.
Discussions that performed work without a confirmed outcome
1
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Leading evidence: 'Run over a raccoon' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Run over a raccoon' (1 discussions). For that action, 0 discussions report a resolution and 0 report an unsuccessful attempt. No action has an explicit, attributable resolution report under the current rules. These are forum reports and suggestions, not a confirmed diagnosis.
Source reports, not a diagnosis or a success probability. Counts refer to discussions and can overlap.
Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.
Discussions that contain suggestions
1
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Suggestion · Original poster
Other than those few rare occurences, the transmission and everything else run very smooth.
Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.
Discussions that contain suggestions
1
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Counts describe captured discussions, not unique people or a diagnosis. Author identities are not reliably stored. Exact duplicate evidence is counted once across matching discussions; one discussion counts at most once per action/state. Multiple repairs reported together remain a combination. Suggestions and failed attempts do not establish a fix. Matches cover whole discussions and can include related faults, model variants and incomplete threads.
14 eligible posts · 0 unverified posts · 1 discussions match the subject in their title or opening post.
Rennlist: 1 discussions
0 evidence records excluded for query context · 0 excluded by outcome qualification · 0 adjusted by outcome qualification.
0 acknowledgements have no verified action link; they do not establish a repair result.
Generation: 20261026T135432Z · outcome-qualification-6. Deterministic extraction; no AI model inference. How we use sources
I've been hearing this strange noise under the car, but it's only happened like 3 times in the last several months since I first heard it.
The noise sounds like it's somewhere right behind me and under the car. Seems to be in front of the engine area.
It doesn't sound like the engine, more like the transmission or driveshaft.
To describe it...Sounds like "a chain slipping off a sprocket"...or gears slipping?
Or like the sound when you accidentally shift into Reverse when you've moving forward, except it's not that harsh.
It lasts only a second, then it's gone and I'll never hear it again in a long time - weeks, or months before the next occurence.
Has always happened when I'm accelerating slow and gentle, like moving off from the lights.
Gives me the feeling that the car is moving in a higher gear than it's supposed to be, then as it downshifts, there's the split second grinding noise.
Or it could be the noise first, then the downshift...I can't be sure as I've not had the chance or enough time to really analyse it when it happened.
I tried to intentionally replicate the noise, by moving at higher gear, but it doesn't happen.
It also doesn't happen when I'm accelerating hard or downshifting aggressively.
Other than those few rare occurences, the transmission and everything else run very smooth.
Has anyone experienced this before? I'm thinking it could be early signs that I need a transmission service?
I sure hope it's not the transmission going bad...
It's a Tiptronic 2002 C4S @ 80600miles
Thanks.
Cosmos - Does this ever happen in reverse? My car makes a sound that I believe is similar to yours but it does it mostly in reverse or if the car downshifts to first abruptly. When I reverse, I hear two pops along with shaking of the car, I believe it is diff related. I am going to inspect this weekend and see if I can see something obviuous like an axle joint or loose bolts on the suspension. I will get back with my diagnosis, I am scared it is my diff!
No, Tippy. I've never had it in reverse, only in those rare instances as described.
I think I'll consult my mechanic and also schedule a transmission service,
have been wanting to do that in a while.
The more I read your description the more I believe it is the same in my car, the only difference is mine is usually on quick throttle burst in first gear when there is slack in the driveline. If I footbrake (hold the brake and give slight gas), the driveline will not "pop" or grind then.
Hmm..maybe mine's the early stage of a similar problem like yours...?
But I don't have any "popping" sound on mne though.
And like I said, when I push or drag the gears, it's smooth.
yes sir
get the car in the air and pull of the plastic panels
use a pry bar to move the mount
if you see tears in the rubber its time for a new mount
pretty common complaint and 80k miles is about the right time for one to wear out
