Alrighty, so I'm pulling the cell codes off and this is what I get. ! = light on for 3 seconds. = light off for 1. !...!.! I don't know if the long pause is between codes or to divide the ones and tens up. If it's a 10, and 20 code then what should I check for the 20, grounds? I already got a new IAT sensor but it didn't change anything even after resetting the ecu so I think it might be the circut for that. Any help? I know my o2 sensor is bad, do you use a 4 wire o2 for obd1? Using a p28 ecu btw.