Have you pulled the fault codes yet? If not, do you know how to do this yourself?
Ok, we need to do that first before throwing any more parts at. Accurate diagnositics is critical in repairing the problem and not costing you a fortune in replacing parts that are actually good.
To extract a trouble from the computer for diagnostic purposes, the Assembly Line Communication Link (ALDL) connector is used.
Ground terminals A and B with the ignition "ON" and engine not running. The system will enter the diagnostic mode. In this mode, the computer will display a 12, three consecutive times, by flashing the "CHECK ENGINE", "SERVICE ENGINE SOON" or "MALFUNCTION INDICATOR LAMP" or light. A 12 consists of one flash, a short pause, then two flashes in rapid succession.
After 12 is displayed, any stored trouble s will be displayed by flashing the "CHECK ENGINE", "SERVICE ENGINE SOON" or "MALFUNCTION INDICATOR LAMP" light. All s are displayed 3 times each then a 12 will repeat. In the diagnostic mode, the computer will also energize all computer controlled relays and solenoids.
ALDL Connector (Located Front seating area, driver side, under dash, mounted near fuse panel )
Once you retreive the codes, if you have a question on either diagnosing the code or replacing a part, just re-open this question and I will continue to help