What's going on.....?

[Jetta Jockey]

Every o(u)nce in a while my car will give out a big puff of dark (fuel) smoke while driven at a steady high rpm (no tach), speed is usually around 80 mph. Engine will rev ever so slightly and the car will actually feel like it is going faster for the split second it takes for this anomaly to transpire.
Someone told me it was fuel impurities getting burned up in the combustion chambers. It seems like this occurs more often when I don't put any fuel additive in at fill up. Any ideas?

[chrissev]

Every o(u)nce in a while my car will give out a big puff of dark (fuel) smoke while driven at a steady high rpm (no tach), speed is usually around 80 mph. Engine will rev ever so slightly and the car will actually feel like it is going faster for the split second it takes for this anomaly to transpire.
Someone told me it was fuel impurities getting burned up in the combustion chambers. It seems like this occurs more often when I don't put any fuel additive in at fill up. Any ideas?

might be oil getting into the cylinders and burning.

[Jetta Jockey]

Chris, I'm pretty sure this is a fuel problem. The car uses very little oil and the smoke is black, not the blue normally associated with oil burning.
Does anyone know of a reputable place to purchase injectors, rebuilt or new? I think these may have something to do with my "problem". I think at least one of my injectors may be "dripping" fuel onto the glowplug causing it to destruct over a period of time. And possibly contributing to this smokescreen malady.