Car sputters on acceleration

[Will12]

99 passat 1.8t. I washed my car yesterday and changed fuel filter today. The car sputters on acceleration; however, it has power, and idling is good too, no check engine light. I thought perhaps water got into the air filter or beyond, or fuel filter has some air bubbles? Any ideas?

[agmcdonn]

Hi, have you fixed this problem yet? I have the same issue with my '97 1.6 but it just came into the car, I did not do anything with the engine. Another guy I know has the same problem with his '99 1.6 but neither of us were able to get this diagnosed with our mechanics, having tried many times. This is in my car for almost 9 months now and is driving me mad. Please let me know if you have the solution.

[Will12]

Yes, I fixed most of it. First, i noticed that my hose from the air filter got loose and came out, so, I retightened it; also, I changed fuel filter--it's in front of rear axle on passenger side under the black trim. Car accelerates good, but a little sputtering is happening, though, but what was before, I can live with it. And changed air filter too. Filters are cheap, and good start.

[veedubmechanic]

ever replace the power output stage ( ignition module) on top of the air box?

[Will12]

....what does power output stage do; and what is it?