I have a 2002 f350 7.3. It was running fine 2 days ago. After I put some diesel in it my water in fuel light came on. I drained the water out and took all the fuel out and put fresh diesel in it. It starts up fine and idles okay but when I try to drive it it looses all power and acts like it's starving for fuel and almost dies. It was smoking white smoke for a little bit even after I took all the water out but now it's black. I have no idea what it could be.

 

What did the fuel look like that you drained out?

 

Maybe its...

 

It was nasty and had water in it

 

What do you mean?

 

I think he means it's probably starving for fuel...
Where did the diesel come from? If it was full of water and nasty you probably need to be talking to the station you got it from. Black smoke means you're not getting enough air to completely burn your fuel, white could mean water in your fuel, not enough fuel, or something else causing the fuel to burn improperly.
Something is up, and it sounds like it's a fuel problem. I'd start by calling the station and asking if they've had any other complaints.

 

Changed filters? When draining the fuel, where did you drain from?

 

It will run like crap until you've gotten all the water out of the fuel system....Lines, filters, Rails....unless you drain EVERYTHING. and then it will run slightly crappy for a short time until it's all gone.

 

Agreed - Hope you got new fuel at a different station- Try some Hot shot heating oil treatment or similar & let it idle for a hour or so then see how she does.

 

You might also try a fuel additive like Stanadyne that has properties that deal with water contamination. Water is BAD JUJU on injectors big time. If you had it in the fuel bowl it is most likely already in the fuel rails.