DSG Slipping? How to diagnose?

TopCityBMW

Member
Joined
Dec 15, 2020
Location
Missouri
TDI
2012 Sportwagen
How would I know if the DSG is slipping or otherwise having issues? Fluid replaced at dealer approximately 10,000 miles ago. 110k miles on the car.

Recently started jolting? and today suddenly surged to 3k RPM at 10mph without accelerating the car.

What are some things to look for, or test? Should I be looking at DSG clutch packs? Costs? Labor?
 

oilhammer

Certified Volkswagen Nut & Vendor
Joined
Dec 11, 2001
Location
outside St Louis (where it's safe)
TDI
There are just too many to list....
Normally the M-unit will flag a DTC for that sort of thing, and you'll get your friendly MIL staring you in the face. Although a fault may have been detected and not triggered the MIL request. In any event, OBD works, start there.

Did it start working again after that event? Or is it just dead?

Next thing would be to verify the fluid level.

The 02E DSG is a very good transmission. They don't fail. There are sometimes M-unit replacements needed, for a variety of reasons, and rarely the clutch assembly, but more common is a DMF failure (the part that links the engine to the transmission). But when that happens, it is obvious, as the car will no longer move at all.
 

740GLE

Top Post Dawg
Joined
Aug 19, 2009
Location
NH
TDI
2015 Passat SEL, 2017 Alltrack SE; BB 2010 Sedan Man; 2012 Passat,
lowish fluid level would act abnormal and not throw a code.

I ran for a few thousand miles .5L low and noticed a huge difference in operation once topped up.

I drained the excessive fluid off while the engine wasn't running, while it was running it was very easy to get that extra fluid in.
 

TopCityBMW

Member
Joined
Dec 15, 2020
Location
Missouri
TDI
2012 Sportwagen
Normally the M-unit will flag a DTC for that sort of thing, and you'll get your friendly MIL staring you in the face. Although a fault may have been detected and not triggered the MIL request. In any event, OBD works, start there.

Did it start working again after that event? Or is it just dead?

Next thing would be to verify the fluid level.

The 02E DSG is a very good transmission. They don't fail. There are sometimes M-unit replacements needed, for a variety of reasons, and rarely the clutch assembly, but more common is a DMF failure (the part that links the engine to the transmission). But when that happens, it is obvious, as the car will no longer move at all.
It works and drives, just has had these weird issues. I want to say it's done this twice now.
 

TopCityBMW

Member
Joined
Dec 15, 2020
Location
Missouri
TDI
2012 Sportwagen
lowish fluid level would act abnormal and not throw a code.

I ran for a few thousand miles .5L low and noticed a huge difference in operation once topped up.

I drained the excessive fluid off while the engine wasn't running, while it was running it was very easy to get that extra fluid in.
OK. I'll check that. I wasn't aware there was a way to check the level. :unsure:
 

740GLE

Top Post Dawg
Joined
Aug 19, 2009
Location
NH
TDI
2015 Passat SEL, 2017 Alltrack SE; BB 2010 Sedan Man; 2012 Passat,
OK. I'll check that. I wasn't aware there was a way to check the level. :unsure:
the only way to check is to get the fluid up to temp, then pull the plug, if you have nothing come out, try and put some more in until a slow trickle drains out.

Def not an easy way to check the level
 

oilhammer

Certified Volkswagen Nut & Vendor
Joined
Dec 11, 2001
Location
outside St Louis (where it's safe)
TDI
There are just too many to list....
It is super easy. Most modern transmissions are the same way. Far less gray area than trying to read a dipstick going through a long tube while the engine is running. It is a super foolproof method of making sure the transmission is full.
 

Cuzoe

Veteran Member
Joined
May 24, 2017
Location
Los Angeles
TDI
MK7 Golf S
I think you guys are differing on the definition of easy, haha. If the dipstick method was as reliable I would choose that every time for ease. Since it's not reliable (let alone possible) I would call it not easy. Car up to temp, pull the plug and fill until a slow trickle requires a lift/ramps/jackstands and at least one tool. Plus getting under the car... I'll pay someone else to do it. I don't want to get dirty and even a dipstick is already putting me at risk :LOL:.
 

740GLE

Top Post Dawg
Joined
Aug 19, 2009
Location
NH
TDI
2015 Passat SEL, 2017 Alltrack SE; BB 2010 Sedan Man; 2012 Passat,
If you change your own fluid it's easy, if you write checks for the work, it's also easy ;)
 
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