Engine Performance problem
1997 Volkswagen Jetta 4 cyl Front Wheel Drive Manual 156000 miles

Engine runs, but you cannot throttle up or it bogs and dies. You can take off and give it gas slowly and it will come up to speed. Some times it does not want to start, but if you try it 3 or 4 times it will start. It has intermittently started to do this and then was alright, but now you just cannot give it much throttle at all or it bogs and dies. And also can you tell me where the plug in for diagnostic is on this car? I did replace fuel filter and the fuel pressure regulator. Thanks Gary

Very common failure is the ignition coil
I would suspect coil mounted on firewall
check ignition wires
check fuel pressure too

Need a tool or a tester CHECK IT @
http://www.2carpros.com/affiliate/uid/bmrfixit_1
need manual CHECK IT @
http://www.2carpros.com/kpages/auto_repair_manuals.htm