Gearbox not engaging

[Plastefuchs]

Hi all,

I've got an odd issue for you to solve

After changing the transmission fluid after the last major service my T5.1 has developed a persistent issue with selecting any gear when starting up the van - R or D. If the issue occurs and let's say you put it in D, it doesn't have gears and just rolls... if you up the revs it will eventually reconsider what it was meant to do and wacks in the gear, sending a Bing bang throughout the car. Now to the circumstances as to when this happens! It never does it when the engine is cold or at running temperature and only occurs when lets say coolant temp is going down after engine has been turned off for a few minutes (at the shops scenario), anywhere between 40ish to 80ish degree collant temp. Van does not throw any faults when it does happen. But it gets more odd, don't worry! As I have experienced this now for the last 5tkm I have worked out when you come back to the van and start the engine which has slightly cooled down and it has the issue, I can turn the car off and on again and the van has no issue finding its gears... so yes, easy work around but still super odd and annoying! Gearbox runs smooth as between all gears once she is up & running. What are your thoughts? Low transmission fluid after the oil change? Does the gearbox need relearning? Much appreciated your input to solve this!!! Thank you

 

[manfrotto]

Was the fluid changed following the correct procedure and with the correct (approved) fluid?

 

[Hilly64]

I have recently had dsg selector replaced under warranty, 2019 t6 70k. slightly different issue in that it wasn't registering P and would allow key to be removed when not in park. diagnoses was play in the selector not engaging the micro switch. If you have any sloppy play that could be an issue but if it coincided with the oil change then maybe that indicates service related. I am aware the oil change is not a straight forward process

 

[Plastefuchs]

Was the fluid changed following the correct procedure and with the correct (approved) fluid?

I'd assume so, it's a proper workshop specialised in VW & Audi... but they are only humans too. The one thing I haven't found an answer for is if the standard transmission oil change volume would be the same as transmission fluid change / refill after the mechatronic was off. Would the mechatronic hold the oil when draining the old fluid or does it drain with the rest? Is there a different procedure to refill when mechatronic was off?

 

[manfrotto]

I'd assume so, it's a proper workshop specialised in VW & Audi... but they are only humans too. The one thing I haven't found an answer for is if the standard transmission oil change volume would be the same as transmission fluid change / refill after the mechatronic was off. Would the mechatronic hold the oil when draining the old fluid or does it drain with the rest? Is there a different procedure to refill when mechatronic was off?

The issue you have sounds like a sticking solenoid or similar, possibly from the incorrect fluid, but if it was done at a VW specialist you would hope they did it all correctly.

There are two drain plugs - one for the transmision and one for the Mechatronics. The fill procedure is done with the fill level check via the transmission drain (it has a pipe that screws in inside the drain hole).

There are a few good youtube videos for the procedure.

There is also a "relearning" process after a change, but I don't think it would resolve the issue you are having