DSG Shift Problem in Full Auto

[Rinzleristron]

I've had a problem with my '05. Apart from it being a complete pile of **** and recently needing a replacement engine, my DSG for been playing up for some time. In sequential, stick or paddle, it changes up and down the gears without any issues and as smooth as you'd expect. The problem is in Auto, it's reluctant to change up past 3rd/4th and will go right up the rev counter without shifting and I have to use the paddles. It seem to be intermittent. The filter and oil were changed on the weekend but unfortunately it's not had any effect.

Anyone got any idea what it might be and how to solve it?... other than with fire.

[david85williams]

I've had this problem. Turns out it was a rear wheel speed sensor. The castellations on the hub were heavily corroded giving the speed sensor a bad reading. A quick (temporary) fix for me was to take the sensors our and clean them, they get pretty dirty. Mine got to the point where occasionally the ABS light would come on. Ironically when this happened the auto gear change worked perfectly!

[Pesky jones]

Another vote for the wheel speed sensor. Had the same symptoms

On the hub of our cars, the hub bearing has a metallic strip that goes round the bearing. A correlating sensor then reads off this strip. The readings play a part in tyre pressure, speed sensor, ABS, traction control etc. The strip can corrode and give false readings. On a manual car this would lead to problems with what Ive listed, but as DSG, it also affects the gear changes.

The strip around the bearing, or even the bearing itself, can't be replaced seperately unfortunately - you'll need to buy a new hub. Around £130. Do go genuine, I bought a LUCAS hub from Euro Car parts and it eradicated half the issues. Got a hub from VW and it fixed it entirely.

Can you scan it with VCDS? it will show which corner is the offending corner hopefully

[david85williams]

Just to also add if the wheel sensor is getting a false reading (the wheel is going faster or slower) it thinks the car is turning. With DSG it will try to avoid changing gear whilst going around corners (depending on the corner and speed).

[Pesky jones]

Just to also add if the wheel sensor is getting a false reading (the wheel is going faster or slower) it thinks the car is turning. With DSG it will try to avoid changing gear whilst going around corners (depending on the corner and speed).

Hence the high revs...nice! I had always thought that if the car thinks its wheels are going different speeds  its no wonder the gear changes get mucked up - had never taken the next step of thinking about why. That explains it nicely!

[Juliand]

Bookmarked this for future reference (Fingers crossed won't need it, but you never know with these cars!)......Such knowledgeable and helpful people on here. I wouldn't have made the connection to wheel sensor/s. Brilliant resource! 

[Rinzleristron]

Cheers all, I'll check it out over the next few days. Hopefully it is down to the speed sensor. May change the rear bearing etc. while I'm there. Interestingly enough my ABS, Tire Pressure and TC lights are all on. Thanks again. I'll update if my advice based tinkering eradicates the issue.

[Pesky jones]

Hopefully it is down to the speed sensor. May change the rear bearing etc. while I'm there.

I think your problem is not the sensor, more the metallic ring around the bearing the sensor reads off, which is intergal to the hub. 

Interestingly enough my ABS, Tire Pressure and TC lights are all on.

As mentioned these are symptons of a failing connection between sensor and the metallic ring. Im 99% you will need a new metallic strip which ultimately (as discussed above) means hub

[Rinzleristron]

Hopefully it is down to the speed sensor. May change the rear bearing etc. while I'm there.

I think your problem is not the sensor, more the metallic ring around the bearing the sensor reads off, which is intergal to the hub. 

Interestingly enough my ABS, Tire Pressure and TC lights are all on.

As mentioned these are symptons of a failing connection between sensor and the metallic ring. Im 99% you will need a new metallic strip which ultimately (as discussed above) means hub

Any idea what size hub I need to be looking at? 30mm or 32mm. I did read somewhere that going on the reg no. is not reliable. I hope it's not a case of stripping it down to see what size hub is fitted.

[Pesky jones]

Yep it is a case of stripping down to find out. I remember finding the majority of the gti models were one size, but I xant remember which! Even then I wouldn't be 100%.