Final post - I have driven over 500 miles now since adding BG 44k and it was well worth the cost. I cleared the codes for lean mixture on left and right bank and they have not returned!! The code for the intake air temp sensor has not returned but I will replace the MAS sensor this month anyway. Best news is that the blue smoke I had for several days on start up must have been "junk" being cleaned out of the engine and fuel system as it has not reappeared over a week. Engine ideals smoother and has more power. I recommend this cheap fix for many problems we deal with! Happy Holidays to all!