Smoke???

[02stroker7.3]

Hey everyone new to the forum and to diesel trucks. I have a 02 7.3 that I've owned for. Little over a month the truck has 143000 on the odometer. I have just noticed smokes in 2500-3000 rpm range even when the engine is warm. This doesnt happen everytime just occasionally. The smoke is grayish to almost white in color so im assuming this is unburnt fuel. The truck does not smoke any other time and ive removed the oil cap and sat it on the fill hole and it does not get knocked off.It does puff smoke from oil fill. Any ideas ?
Really got my fingers crossed I'm not in for a major repair on a truck I just bought

[Dietoremain]

sounds like you may have a leaky injector..