your exhaust system joins to one pipe on the rear of the engine and only separates into duel exhaust after the catalytic converter, so smoke on one side is not really an indicator that a certain bank has a problem. white smoke usually indicates some kind of fluid entering the engine through the intake system. these engines are notorious for developing engine coolant leaks in the intake manifold. The EGR valve directs exhaust gases through the lower intake manifold then through what is called a stove pipe through the upper intake manifold (which is made of a thermo plastic) to the intake air stream. This "Stove Pipe" gets very hot and will eventully melt the upper intake manifold which has coolant flowing around the stove pipe. I had this problem. got the lean code, with no real problems, then pow, white smoke and very soon an engine which will not run. The repair, if this is your problem is pretty easy with minimal engine knowledge, and a good repair manual. and NAPA has a great upper manifold with revised stove pipe. the problem is trying to see if coolant is in the intake manifold behind the throttle body and some disassembly is requirid to confirm if this is your problem.