You'll have to look at the symptoms to figure out where to go next. If the engine doesn't crank with the ignition switch, the circuit feeding the switch is the place to start. If it DOES crank from the ignition switch but doesn't start or run, usually it's a sensor problem. Having the diagnostic fault codes read is the place to start but you would need a scanner or code reader for that, or if you can tow it to an auto parts store, many of them will read engine codes for you for free. Fault codes never say to replace parts; they only indicate the circuit or system that needs further diagnosis. The sensor will be bad about 50 percent of the time. Wiring and connector problems account for the other 50 percent of the problems.
General Motors is extremely selfish about allowing independent shops to work on their products, however, the government has mandated that anyone be allowed to work on emissions-related stuff, and that includes anything to do with the Engine Computer.
Tuesday, May 29th, 2012 AT 8:58 PM