First of all, you gotta stop listening to all those people telling you to replace this or that without ever looking at the car. You already recognize that the most expensive and least effective way to diagnose a problem is by throwing random parts at it. Besides wasting money, that introduces a bunch of new variables because no two sensors are exactly the same. Your Engine Computer has to learn the characteristics of the sensors. That doesn't always happen right away, and until it does, running problems can develop.
What you need to do is got hold of a scanner to see exactly what it is that's setting the codes and turning on the warning lights. GM has had a lot of trouble with play developing in the front wheel bearings in as little as 15,000 miles. That play is normal but it causes the signals to drop out from those two wheel speed sensors. That makes it look like a wheel stopped spinning. The most common symptom is unneeded ABS activation when slowing down, but if that signal drops out during acceleration or cruising, the ABS Computer will think there's a problem with that sensor. That's when it turns the traction control function off and turns on the light. There should be a diagnostic fault code related to that in the ABS Computer.
Chrysler has entire books on what to check for every fault code, and I'm guessing GM does too. You might try asking at a local dealership if they have such a book. Often the service advisers will photocopy a bunch of pages for you. The manufacturer's service manuals also have troubleshooting procedures and they spell out how to test sensors. Since you're working with numerous different systems and problems, the service manual would be a better investment than more parts to try.
Friday, April 27th, 2012 AT 4:15 AM
