I have a 03 volkswagon passat 2.8l i recently did a motor swap I had the car running and driving down the road it stalled out on me when I was driving it sorry got it back to the house and found out what was making star which was the intake hose fell off and then after that you put it in gear and it will not move at all no reverse no drive or 1st or 2nd nothing
Well the intake hose might have come off because it back for it I would assume there's something serious wrong if it won't even move now. I advised against people trying to rebuild those things because they're high-tech monstrosity and you get into a giant rats nest working on them. They're not vehicles you can rebuild yourself unless you're trained Volkswagen technician with noodles expensive tools and software
All I did was swap the engine and everything was working fine until the intake hose fell off and then it to stall out and wouldn't start after that and then I discovered that the intake hose is off start it up and now it won't move I did not rebuild anything other than swapping a motor