First, I would completely drain the fuel tank and put in 5 gal of diesel from a reliable source. Dump in some Power Service and then go drive the snot out of that wagon. Lots of 0-60 maximum performance accelerations, long hills at WOT...if it's not any better after that, I'd be looking for a diesel injection shop to do a pop test on those injectors.

What does that smoke smell like? If it's Pepe' Le Pu, you're burning oil and you either have a broken ring, bad valve guide or a cracked piston. If it's a diesel spilled on the ground smell, you have a bad injector.

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Never a dull moment at Berry Hill Farm.