15 WRX, 52k miles, Cobb intake, verticooler, Grimm EBCS, TGV deletes, EGR delete, perrin water pump and crack pullies, Tried to fix Extreme Lean at idle (maxes out AF correction positive 35 at times) by buying new OEM MAF, Cobb MAF extension harness and front O2. OEM MAF connector was corroded, bought new connector with new pigtail, cut OEM wires, no change. 1st log in parking lot cold start 40 mph. 2nd log getting on high way then cruise. 3rd pull on highway cruising watch extreme rich (20 negative AF correction) makes no sense. Random.