[JHALL]

I've searched for this complaint, but everything I've found is on start up and 99% of the threads are with 6.0's. And I didn't put it under problems because I don't actually know if it's a problem or not.

I have an early '99 F-250 7.3 w/ just under 200k. I bought it just last week, and it already has a Superchip tuner installed. It was set on the performance/tow tune and I just bumped it to the Hi-performance tune the other day (even though it is not that impressive). With either setting, under hard/full throttle it sometimes blows a little bit of white/greyish smoke, then stops. It's usually only a once or twice thing every outing. The majority of the time it's pure black smoke. But under light throttle, no smoke at all. And on start up there is no smoke what so ever, and starts right up. I'm not losing power or anything. I'm not sure when the fuel filter was last changed, could this be a possibility? What could cause white-ish smoke at times and black smoke the rest? Any ideas? Thank you!!!