How can I diagnose a fuel delivery problem on a 2003 VW Jetta GLI 2.8L

SOURCE: vw polo electrical problem

If spark is good, it could be fuel pump or filter, or even your solenoid. Message me with more info. does it:
1. Try to start? - Fuel issue, or battery issue?
2. Click - Battery issue
3. Nothing? - Solenoid issue

SOURCE: 2003 vw jetta tdi fuel filter

It is on the passenger side right behind the washer fluid fill tube. You can follow the fuel lines (look like 1/4" black tubes, some are clear) from the injector pump to it. It is a caniser a bit bigger than a normal looking oil filter and sits between the washer bottle and the metal that forms the wheel well. It is held in by a screw type clamp about half way down the cylinder. Probably isn't the fuel filter unless there is air in the lines to the injector pump or they didn't bother to fill the fuel filter up with diesel after putting it in. There is not a fuel pump in the tank in these cars so everything is sucked up by the injector pump and it needs to be primed properly.

SOURCE: 1999 VW JETTA anti-theft alarm keeps going off & car won't start

pop the truck and the alarm will disable

SOURCE: 2003 Jetta 2.0 L Engine, MIL and EPC Lights ON

Probably a bad COIL-PACK

SOURCE: Why does my 91 VW Jetta stall out and lose power while driving?

I had a similar problem and the mechanic diagnosed it as a problem with the ignition coil. So you might want to get that checked.