This is the 2nd time I have seen a white puff from my exhaust. 2 times when shopping etc, with someone in truck for 20 minutes or more (goofing off), but when I come back to the truck and take off I see a white puff from the exhaust.

I have tried repeatedly to get this to happen at start-up and it won't happen. I rev the engine, and it still doesn't happen. I back up, still doesn't happen. I only see this after long idle with the A/C running and then its gone. When I say it's gone, I can't see it anymore while driving or at stop lights it's literally gone.

I'm leaning towards changing my pcv valve(?) My oil isn't milky, don't smell fuel. Checked my coolant levels, everything looks normal to me and I'm not burning oil (I use full synthetic and still change it @ 3500 miles)

Now, my exhaust isn't stock, it a flowmaster with dual exhaust and I wonder if that has something to do with it as well.

Pulled 6 plugs (didn't bother with the hard ones in the back) and every single plug looks brand new, gap is still fine.

**Honestly, I'm going to chalk this up to moisture vapor from the exhaust, I don't see anything wrong mechanically.

Specs:
2003 DODGE RAM 1500 QUAD CAB PICKUP
Make: DODGE
Model: RAM 1500
Trim: ST Quad Cab
Color: BLACK
Engine: 4.7L
Fuel: Gasoline
Transmission: 5-Speed Manual
Drive: RWD
3.55 Rear Axle Ratio
Corporate 9.25 LD Rear Axle
Two Wheel Drive (2WD)/(4X2)
6 FT. Cargo Box
Miles: 139000