i have a 2002 diesel beetle that won't start. it sounds like it's going to start (the engine actually catches for a second) and then it stalls. i took it to my machanic but he can't figure out what's wrong with it. any ideas?

There are a variety of possibilities, here's a link to a good DIY troubleshooting guide.

http://tdiclub.com/TDIFAQ/TDiFAQ-8.html#b1a

I had exactly the same problem about two months ago. I tried everything I could think of to start the car. Went to every website I could find. Even read the owner' manual! I finally had my 2003 TDi towed to the local dealer. When I told the service advisor my problem (it would turn over, try to start, then go dead - repeatedly), he asked me to pop the hood. He reached behind the EGR valve (near the firewall on the left center as you face the engine) and tripped the reset switch. The car promptly started! Advisor said that the diesels have the EGR valve that needs to be cleaned out every so often - and he suggested that I have mine cleaned and that would fix my problem. I was pissed - since I had just had the vehicle in for a 45,000 mile service and they said nothing about a potential clogged EGR valve - nor is there one word in the owner's manual or on the VW website about this. Might want to check this out. Good luck.

In europe the diesel fuel is alot more pure and carboning of the intake system is not a problem. Carboning can also occur if you do alot of short trip driving and stop and go driving.

I have the same problem with my 2002 Beetle TDI. I started using One Shot (stanadyne) when I fill up with fuel and the problem is under control. If I stop adding it I eventually have problems again (after a couple thousand km). I think the injectors gunk up or something.