Hey Ivaz, which corolla did you install the CAI into? I want to do the CAI/Custom Exhaust combo and have been reading up about it the last few days. I was assuming that the INJEN CAI had some issue with the 08 model ZRE's and threw the CEL, however after looking through members threads and other threads, i came up with a little table. The majority of ZRE owners have not had an issue with it. So im guessing, could it be possible that there was a bad batch of INJEN CAI's? John, Dwee and Tom, did you guys all purchase the CAI off the same seller at the same time? Facelift benyip - ascent - No CEL itsmehuey - ascent - No CEL uMmmz - Levin ZR - No CEL 2009 dutchie101 - Levin ZR - No CEL dwee. - Levin ZR - No CEL (happened once) 2008 shin0bi - Ascent - CEL johnnieboi -Levin ZR - CEL justchris - Ascent - No CEL mastercuong. - Ascent - No CEL JE-55-EA - Sedan - No CEL 2007 flipsta24 - Levin ZR - No CEL vs0p - Levin SX - No CEL