The other day I noticed white smoke in the passenger side exhaust on start up. It's ONLY the passenger side, nothing on the drivers side. It doesn't last long (just until the engine is warm) and only happens if the truck has been sitting overnight.

I never noticed it before and the only reason I noticed it this time is because I had to get out of the truck to get something right after I started it.

The engine runs a little rough on start up but smooths out before I even get to the end of the block.

While trying to figure this out I noticed a few air bubbles in the IP return line before a cold start.

The engine runs fine otherwise. No blowby.

What the heck would make the smoke come out the passenger side only, and do the few (VERY few) air bubbles in the IP return line have anything to do with it?

While we're at it, how do you go about locating such a tiny air leak in the fuel system?

Thanks