Smoking and Running Rough

What color smoke? White is usually leaking water. Blue or greyish is leaking oil.

The smoke is whitish and there is litte water comming from the tailpipe.Put a new o2 sensor in and that stopped the ruff idle but still quite abit of smoke.

Just on start up or does the smoke go away after the truck runs?

Sounds like a HG problem. Does the exhaust smell sweet? Is there any mixing of water/oil in the crankcase or radiator? It is my understanding that 4 cyl. motor will show water in the oil before it will show oil in the water.

Hope this helps. Maybe someone else will chime in with thier two cents.

its the headgasket leaking into the cylinder ~ vaporizing the coolant thru the exhaust (classic 2.6 problem) mine just did this. Get the head pressure tested for cracks when you do the gasket. It about a 7bill job at a reqular shop.