What mods do you have and what have you done to it lately? Anything unusual happen lately besides the CEL. Any service work? Check to make sure the A/C is not draining directly onto the 02 harness which is zip tied to the side of your tranny. Your best bet is to take it to the dealership and let them hook it up to the computer. They can pinpoint where the issue is coming from. Worse case scenario, you'll need a new wiring harness. Yes, that means all new wires. I know someone that has gone thru 5 until he had one that worked. Alot of time at the dealership!