I know you were saying you were getting a lean code, maybe a lean at idle code? Could you go get that re-read and give us the actual number? Also, do you have a boost gauge of any kind? Does it read vacuum? What is the idle vacuum reading (in inches)? Is it steady or does it wander? It will change a bit when your A/C cycles, but I'd like to know what the gauge is saying and what the actual CEL code number or numbers are.