Missing when warms up

[snowman4evr]

Hi All, My truck has been experiencing this problem ever since it was purchased about a month ago now. It will start up fine, plenty of power and runs great for about 20 miles, then it will develop a miss to beat the band. When I got it home the other day I had my girl listen to the exhaust outside while I kept it reved 2000 rpm. It actually sounds like a backfire and she said it blows black smoke when it misses. Any ideas? Iam thinking IP going bad when it heats up.
Its not throwing any codes.

[racer55]

It is more economical to try a PMD relocation kit first,besides if you plan on keeping the truck for any amount of time it is good practice to have a spare PMD ready for roadside emergency's.

[Robyn]

Change the fuel filter, then be sure that the lift pump will push fuel out the water drain hose with the engine running.

If the engine dies when the water drain is opened then the lift pump is not working.

Keep us posted

Missy