i have a 2.0L 2000 jetta and it did the same thing, I had to have the throttle body and 02 sensor replaced.
I have a 1992 Escort, and it starts doing that right around the time it needs its 30,000 mile check-up.
Probably the fuel filter. Change it.
yes, you are causing it to run richer.
Check your tensioner
If you have replaced plugs and wire most likely one of your coil pack usually run about $50
Could be a turbocharger, or a low oil level in a manual transmission causing it to "howl".
It's a good possibility that the old oil was never drained, then the new oil added. Now there is way too much oil in the engine causing the sputter.
the reason an engine "jerks" is because all of the fuel going into the cylinders are is not completely burning thus causing a loss of power...
you need a scanner to scan your cars computer to see what is causing it to happen
Check just in front of the muffler. The pipe that connects the muffler and the catalytic converter went on my 97 GTi, a portion of the exhaust system was sitting on a support causing a rattle sound when accelerating.
It may be your spark plug wires. I had a Honda that hesitated when going up hill or when accelerating and it ended up being that the spark plug wire insulation had some hair line cracks causing the wires to short. I replaced the wires and havent had the issue since.
look at your vaccum hoses 4 leaks.