Hey guys, ive done some research by using the search function and also google but i havent found anything of real substance. My codes are p1130 - Lack of Upstream Heated Oxygen Sensor Switch - Adaptive Fuel Limit - Bank No. 1 p1131 - Lack of Upstream Heated Oxygen Sensor Switch - Sensor Indicates Lean - Bank No. 1 p1150 - Lack of Upstream Heated Oxygen Sensor Switch - Adaptive Fuel Limit - Bank No. 2 p1151 - Lack of Upstream Heated Oxygen Sensor Switch - Sensor Indicates Lean - Bank No. 2 What does adaptive fuel at limit mean? Since all these codes are coming at the same time i doubt its an O2 sensor because i doubt they would both go bad at the same time. On my car i have a CAI, Longtube headers, o/r prochamber and a catback. I also have an SCT tuner from americanmuscle.com to make everything run better (i also had MILs on the rear O2s before the tuner). I had the codes p1131 and 1151 before and was told to do the easiest thing which was to clean the MAF (all i did was get MAF cleaner and spray it in there, how would you clean then the connector part?). The codes went away for a couple weeks. I just recently started feeling a rough idle. Doesnt die or anything but it fluctuates, and then the codes came on. From what i researched it could be vacuum lines as well. Which lines are vacuum lines? i have no clue. If some one could post a pic of an engine with the vacuum lines circled or something that would be great. Do you think it might also just be an IAC? Where do i get a new one of those and instructions on install? Might there also be a problem with the tune? Ive got the preformance and economy 93 octane tunes. Any help would be amazing. Thanks.