Gearbox malfunction [still?!]

[GordonS4]

Hey everyone, so I've made a post in the past year about my B8 S4 with the gearbox malfunction but it doesn't seem to go away. After originally replacing the circuit board, that fix only lasted about 10 months before the car had the code again. I opted to pay for the pricey fix and got the mech unit replaced but that didn't last long, (within a couple weeks) the code comes back up. My mechanic has readapted the car twice now so I'm not sure how to move forward from here. The code (at the moment) goes away every time I restart the vehicle and I noticed that there's an engagement issue where after reversing, if I go back into drive, the car takes a while before it can move (and if I dare to give it gas, it would jerk extremely hard). I tried to put the car onto drive after reversing (recently) and it could not move at all and the "gearbox malfunction" pops back up (restarted it and went away). If anyone can give me insights on what else I can do to fix the car, please do. I will bring this back up to my mechanic but I honestly don't know if he knows what the issue is since I've brought it to him so many times.

TL:DR

Gearbox malfunction comes up, replaced entire mech unit but issue is still reoccurring. The car also has a very delayed engagement from reverse going into drive. (but does not have issue going into reverse from drive).

Thank you !

p.s I understand that doing an entire transmission swap can be a fix potentially, but am trying to avoid that until necessary

[fastboatster]

Probably the clutch is worn, if you drive in heavy urban traffic (stop and go), not surprising. Any actual codes?

[TC_S4]

What error codes you had prior changing the circuit board? What codes you had prior changing the mech unit? And what code you have now?

[GordonS4]

I recently bought a vagcom but don't have a windows laptop to use it with :( so I wasn't able to pull any codes. I do have a foxwell ob2 reader but it said no codes to be found. I'll ask my mechanic about the clutch but I didn't think clutches for auto's would need changing like that but will bring it up forsure. Thank you for the suggestion boatster !

[GordonS4]

What error codes you had prior changing the circuit board? What codes you had prior changing the mech unit? And what code you have now?

before changing my circuit board my friend was actually able to pull the codes for me since I didn't own a vagcom

9708 - Sensor for Gear actuator 2
P171E1 00 [104] - Mechanical Malfunction
Intermittent - Confirmed - Tested since memory Clear
Freeze Frame:
Fault Status: 00000001
Fault Priority: 2
Fault Frenquency: 2
Reset Counter: 40
Mileage: 111813 km
Date: 2019.12.26
Time: 19:55:16
9712 - Sensor for Gear actuator 2
P171E1 00 [096] - Mechanical Malfunction
Intermittent - Not Confirmed - Tested Since Memory Clear
Freeze Frame:
Fault Status: 00000001
Fault Priority: 2
Fault Frequency: 1
Reset counter: 40
Mileage: 111813 km
Date: 2019.12.26
Time: 18:44:20
8030 - Cooling Oil Valve
P179D 00 [232] - Electrical Malfunction
MIL ON - Intermittent - Confirmed - Tested Since Memory Clear
Freeze Frame:
Fault Status: 00000001
Fault Priority: 2
Fault Frenquency: 11
Reset Counter: 40
Mileage: 111813 km
Date: 2019.12.26
Time: 14:58:38

but then after the gearbox malfunction came back up again my mechanic never really told me the codes and just worked on the car, will try to see if I can get a update on any codes that are present. thanks for the reply TC_s4!

[TC_S4]

before changing my circuit board my friend was actually able to pull the codes for me since I didn't own a vagcom

9708 - Sensor for Gear actuator 2
P171E1 00 [104] - Mechanical Malfunction
Intermittent - Confirmed - Tested since memory Clear
Freeze Frame:
Fault Status: 00000001
Fault Priority: 2
Fault Frenquency: 2
Reset Counter: 40
Mileage: 111813 km
Date: 2019.12.26
Time: 19:55:16
9712 - Sensor for Gear actuator 2
P171E1 00 [096] - Mechanical Malfunction
Intermittent - Not Confirmed - Tested Since Memory Clear
Freeze Frame:
Fault Status: 00000001
Fault Priority: 2
Fault Frequency: 1
Reset counter: 40
Mileage: 111813 km
Date: 2019.12.26
Time: 18:44:20
8030 - Cooling Oil Valve
P179D 00 [232] - Electrical Malfunction
MIL ON - Intermittent - Confirmed - Tested Since Memory Clear
Freeze Frame:
Fault Status: 00000001
Fault Priority: 2
Fault Frenquency: 11
Reset Counter: 40
Mileage: 111813 km
Date: 2019.12.26
Time: 14:58:38

but then after the gearbox malfunction came back up again my mechanic never really told me the codes and just worked on the car, will try to see if I can get a update on any codes that are present. thanks for the reply TC_s4!

From your scan, they should know from the start that replacing the circuit board wouldn’t solved you issue. They’re 3 error code, only one, P179D is associated with the circuit board.

The two others codes, is related to mechatronic units itself. After, replacing the mech unit did your mechanic updated the tcu software to match the new mech? Most of the indy don’t have the tcu update, so need to go to the dealer to perform the update.

Maybe the new mech unit is defective? You really need yo rescan to see if it’s the same error.

The last solution, is to find a used transmission with low mileage and swap the tranny complet.

[Keymainey]

Hey, actually the 179E code deals with the gear position sensor as it states in the description so it will not be fixed with the mech unit. It's a small sensor buried deep in the trans unfortunately. I had the issue early last year. I was getting that code and 179F. If that same code pops up then that's what it is. The behavior doesn't sound the same as what I had and what others have said. With these trans though, you never know what's normal behavior for any conditions. Just google search gear position sensor audi s4 and there should be more info for you. 214459

[fastboatster]

Hey, actually the 179E code deals with the gear position sensor as it states in the description so it will not be fixed with the mech unit. It's a small sensor buried deep in the trans unfortunately. I had the issue early last year. I was getting that code and 179F. If that same code pops up then that's what it is. The behavior doesn't sound the same as what I had and what others have said. With these trans though, you never know what's normal behavior for any conditions. Just google search gear position sensor audi s4 and there should be more info for you. 214459
Yes, but he had p171e1, not p179exx. Gear ACTUATORs are the “shift forks” on the mech unit, their position sensors are on the mech. Selector lever sensor is the thing you are referring to. Yes, total PITA but OP doesn’t seem to have problems with it.

[Keymainey]

You're right. I guess that's what happens when you're tired and skimming through. Just saw the 'E' part of the code really and gear sensor. Disregard my last post.

My guess based off behavior and not codes:
Clutch faulty or worn
Fluids low or old
Adaption

Is there any other symptoms? Is it progressively getting worse? Need new codes to fully know what's going on.

[GordonS4]

You're right. I guess that's what happens when you're tired and skimming through. Just saw the 'E' part of the code really and gear sensor. Disregard my last post.

My guess based off behavior and not codes:
Clutch faulty or worn
Fluids low or old
Adaption

Is there any other symptoms? Is it progressively getting worse? Need new codes to fully know what's going on.

nono, you're good, I appreciate all feedback !
As of now, I've adapted my car twice since the mech replacement and the transmission fluid was done the same time the mech got changed. Definitely leaning towards the clutch being worn
but will definitely try to scan the car for codes asap and update the post !
Also, yeah I feel that the car is progressively getting worse from when I got the car back after the adaptation. (roughly 2 ~ 2 1/2 weeks ago)

[AudiA72011]

nono, you're good, I appreciate all feedback !
As of now, I've adapted my car twice since the mech replacement and the transmission fluid was done the same time the mech got changed. Definitely leaning towards the clutch being worn
but will definitely try to scan the car for codes asap and update the post !
Also, yeah I feel that the car is progressively getting worse from when I got the car back after the adaptation. (roughly 2 ~ 2 1/2 weeks ago)

Did you solve your problem? I have the pretty close problem with my S6. Car is jerking when going in reverse and in 2. gear in RPM below 1k when i press the gas pedal to accelerate a little he vibrates/jerks and the he stops when he get to a higher RPMs. I have a gang actuator 2 mechanical fail problem. I think its mechatronic.

[GordonS4]

Did you solve your problem? I have the pretty close problem with my S6. Car is jerking when going in reverse and in 2. gear in RPM below 1k when i press the gas pedal to accelerate a little he vibrates/jerks and the he stops when he get to a higher RPMs. I have a gang actuator 2 mechanical fail problem. I think its mechatronic.

unfortunately my problem remains :\ (even after entire mech unit was replaced - costing $4500 with labor..)

my mechanic brought the car to Audi Burlingame (CA) and they're saying that since the problem persists even after the mech was replaced, then it's most likely the transmission itself.. was advised to replace the transmission which would cost $10k just to order. smh.. will probably sell the car for whatever it's worth at this point..

[GordonS4]

Wasn't able to update this post because Audi has been holding my car for nearly 3 weeks.. not really sure what they've been doing to it. My mechanic that I go to thinks the issue is that the new mechatronics is defective but Audi won't honor the warranty to swap it because they don't think it is.

**If anyone knows where I can find a used 2012 Audi S4 transmission please let me know ! I can't find them anywhere except this 100k miles one on ebay

[fastboatster]

what codes are you still getting? My guess is still the clutches but hard to recommend to just replace them because if, say, there's really an issue with the shift fork itself (gear actuator 2) and you pay for all the labor to replace the clutches and it won't fix it, you'll be super pissed. Perhaps 100kmile trans is okay? afaik, landfill had some NSC code transmissions for sale, thought these fit 2012 as well, but not too sure.

[chuckmynorris]

Hey everyone, so I've made a post in the past year about my B8 S4 with the gearbox malfunction but it doesn't seem to go away. After originally replacing the circuit board, that fix only lasted about 10 months before the car had the code again. I opted to pay for the pricey fix and got the mech unit replaced but that didn't last long, (within a couple weeks) the code comes back up. My mechanic has readapted the car twice now so I'm not sure how to move forward from here. The code (at the moment) goes away every time I restart the vehicle and I noticed that there's an engagement issue where after reversing, if I go back into drive, the car takes a while before it can move (and if I dare to give it gas, it would jerk extremely hard). I tried to put the car onto drive after reversing (recently) and it could not move at all and the "gearbox malfunction" pops back up (restarted it and went away). If anyone can give me insights on what else I can do to fix the car, please do. I will bring this back up to my mechanic but I honestly don't know if he knows what the issue is since I've brought it to him so many times.

TL:DR

Gearbox malfunction comes up, replaced entire mech unit but issue is still reoccurring. The car also has a very delayed engagement from reverse going into drive. (but does not have issue going into reverse from drive).

Thank you !

p.s I understand that doing an entire transmission swap can be a fix potentially, but am trying to avoid that until necessary

Hey, a S4 B8 owner here with 178000km on the clock.

I've been having the same exact problem. Especially when it's cold, everytime I go from R to D there is a small delay until it goes into gear. If I step on the gas too soon it get's very jerky and from time to time give's a "gearbox malfunction" notice. It goes away when restarting the engine.

So when I first took it to the shop we ended up installing a mechatronic repair kit, which fixed the problem, for like a week. Then the gearbox malfunction popped up again and this time it only went throu gears 2,4 & 6.
I took it to the shop again and we ended up just taking it to Audi to get the latest update to the gearbox. This fixed the problem for a while, until a few weeks ago.

So instead of replacing the mech unit it looks like we will replace the gearbox completely to a new one. This should go into the warranty (luckily). Probably will end up renewing the clutch as well at the same time. Hopefully this will give plenty of worry-free kilometeres (S-tronic wise at least).

Can't rembember the exact codes what it gave but I have them up somewhere..

[GordonS4]

what codes are you still getting? My guess is still the clutches but hard to recommend to just replace them because if, say, there's really an issue with the shift fork itself (gear actuator 2) and you pay for all the labor to replace the clutches and it won't fix it, you'll be super pissed. Perhaps 100kmile trans is okay? afaik, landfill had some NSC code transmissions for sale, thought these fit 2012 as well, but not too sure.

My mechanic said the codes "were the same" which i'm somewhat skeptical about. He doesn't seem to give me a definite answer/code.. and when he brought it to the dealership, they may have cleared it. I'll see if I can cause the gearbox malfunction popup and rescan it. (Happens pretty easily if I go from reverse to drive without waiting for the drive to engage, car wouldn't move at all even while gassing, I'd have to restart the car). **sorry for asking for advice when I can't even provide the codes [:(] . I'm really tempted to buy the 106k Miles transmission listed on ebay but so conflicted since my current transmission is only at 75k Miles.

will try to update again asap with codes !

[GordonS4]

Hey, a S4 B8 owner here with 178000km on the clock.

I've been having the same exact problem. Especially when it's cold, everytime I go from R to D there is a small delay until it goes into gear. If I step on the gas too soon it get's very jerky and from time to time give's a "gearbox malfunction" notice. It goes away when restarting the engine.

So when I first took it to the shop we ended up installing a mechatronic repair kit, which fixed the problem, for like a week. Then the gearbox malfunction popped up again and this time it only went throu gears 2,4 & 6.
I took it to the shop again and we ended up just taking it to Audi to get the latest update to the gearbox. This fixed the problem for a while, until a few weeks ago.

So instead of replacing the mech unit it looks like we will replace the gearbox completely to a new one. This should go into the warranty (luckily). Probably will end up renewing the clutch as well at the same time. Hopefully this will give plenty of worry-free kilometeres (S-tronic wise at least).

Can't rembember the exact codes what it gave but I have them up somewhere..

Oh wow, this sounds really similar to my problem. If you can find the codes you had please do post it so I can compare them with the ones I get !
Thank you!