plat27265

BoxcuTTer

No, mine is a manual 6 speed. That part number was the result I found via Google search. I'm really frustrated because I asked this Audi dealer for the part number this morning but they keep failing me. I've had their loaner for 10 days now and they haven't even bothered to call me. I suspect they're way overbooked and aren't willing to spend the time to really diagnose this. It's easier to tell me I need a $6,000.00 part.

plat27265

Here's a suggestion: Call the parts counter and give them your car's VIN#. They'll be able to give you the part number for the correct diff. But, based on the Ebay ad I found, it looks like the part number for the Sport Diff for an S4 equipped with a manual tranny is 0BF500043S.

Here's the parts diagram: https://audi.7zap.com/en/usa/audi+a4.../5/500-500011/

To determine which diff you have, look at the PR Sticker in the spare wheel well. Look for the PR Code for the Sport Diff. There are 4 Diff Versions: MFT, MKY, JKS, and MKX. If your Diff has PR Code MKY then the Diff P/N is OBF 500 043S. If MKX, then the P/N is the 'Q' version.

BoxcuTTer

Excellent. Thanks!

BoxcuTTer

Dealer confirmed the part code as 0BF500043S as Plat27265 said. They came back today with quote for a used sport diff for $1,300.00 plus $1,125.00 for labor - which isn't that bad all things considered. It's $450.00 more than the one on Ebay, but if they'll warranty the part they're providing, I guess it will be worth it. I'm still not convinced it's what I need, though.

I called my independent mechanic and he won't do the install as he believes it's some sort of coding issue with the sensor, so I guess my options are 1) live with it until it causes a problem, 2) provide the part from eBay and save $450 or 3) pay what they're asking and have peace of mind.

As an aside, I need to find a new mechanic as well. I've been going to my shop for ten years now and the service has gone downhill considerably. Anyone know a decent indy shop in or around Delaware County, PA?

BoxcuTTer

As of Monday, Audi of Wynnewood will have had my car for three weeks. One week to diagnose, One week to tell me mileage and warranty info. on used part (They will not guarantee labor on the part they are providing. There is only a 6 month warranty on the part from the supplier.).And who knows how long to actually get the work done. Are all Audi shops so slow? I have a loaner, so it's not a big deal - but sheesh.

Hekee

Did you figure it out what was the problem? I have the same fault in my 2009 S4 s-tronic. We also tried to code the sport differental off but it didn't fix the problem.

DynoD

The "implausible signal" description generally indicates that the SENSOR or the sensor WIRING is at fault, not the diff itself. You should challenge the dealer's diagnosis.

adamparkinson

Do you know how to troubleshoot the wiring? I am having the same problem and the sensor was already replaced. I cant imagine the diff went bad.. no oil leak at all

adamparkinson

FYI I identified the IMPLAUSIBLE signal as an issue with my battery ground and some corrosion buildup on the Sports Diff wiring. The sports diff wiring harness terminates in the module near the battery. Once i cleaned the connections all was well with the world!