i have a 2001 A4 Q 1.8T and i can't lock or unlock the door with the remote or button on door but i can lock and unlock with key what is my problem?

 

The door lock motor is bad?? Just a guess...

 

could be the vacuum pump. Can you hear it when you push the button(s) on the remote or in the car?

 

Yeah I would guess it's the vacuum pump.

Push the button (unlock or lock) on your key and check inside the trunk if you hear anything.

 

ok i don't hear any sounds where in the trunk is it located?

 

The vacuum for the 2001.5 (not sure if it's the same for older ones) is located inside the right side panel in the trunk.

You would need to unscrew the plastic panels on the back part of the trunk to access the vacuum.

You could go to the dealer to replace it or DIY.

http://www.audiworld.com/tech/elec149.shtml

 

I'd try to DIY if you can, I hear the dealer charges somethin like $500 for a new one of those things :-X

 

That's what my pump did. so I went to a junk yard and got a new pump for $4, took about 10 min to install and now it works like new again.