BobnOH
not-a-mechanic
No Doc, it's interweb guessing, you done good. We still don't know, continue to try helping.
Couple things strike me, despite what sounds like messed up coolant system you're still able to drive to and from work. Not reading anything about loosing coolant, swapping fluids. I've never experienced head gasket failure in a TDI, but most cars, if you open the coolant system (overflow) and rev the motor, it will blow out coolant.
I also believe the no cabin heat is just a system of whatever issue we have. But rule it out, uncouple the 2 hoses to the core and flush.
Couple things strike me, despite what sounds like messed up coolant system you're still able to drive to and from work. Not reading anything about loosing coolant, swapping fluids. I've never experienced head gasket failure in a TDI, but most cars, if you open the coolant system (overflow) and rev the motor, it will blow out coolant.
I also believe the no cabin heat is just a system of whatever issue we have. But rule it out, uncouple the 2 hoses to the core and flush.