I am repairing a 95 Jetta GL, I was simply changing oil and air filter. After I did so the car would sputter quite hard even turning off the engine at times. So as the process of elimination goes I replaced the spark plugs and nothing. Also just FYI the car was sputtering very lightly before i started. Than I added a fuel injection cleaner and that was no help. I also added some 93 Octane gas just to see if that would help. I checked the distributer cap and and wires and they seemed fine. I even changed the battery to a new one and nothing. So i take the car out on the highway and it runs fine but when I stop at a light sometimes the car will sputter and shut off. I think it has something to do with gas but i don't know. Please Help!

 

I would change the fuel filter. About $23, and located under rear passenger seat area, under the car. Cheap option to try.