I have a 94 cavalier 2.2 Liter, auto trans, vin code 4. I just ran a code reader on this car and got code 27 Quad Driver Module 1 Fault B,code 28 Quad Driver Module 2 Fault C, and code 66 AC Pressure Sensor Error.
I can figure out code 66, but I am lost as to what these other 2 codes mean. Can anyone help me on this?
I found a GM Code book that covers all codes from 1982 to present. Replaced the Oxygen Senson and the TPS. Cleared the codes, Problem solved,
