Code 26 is for a quad driver error, it MIGHT be caused by the ECM (ECM and PCM are the same thing) but could just as easily be caused by something the ECM is controlling. Your 92 can be programmed by replacing the PROM (Programmable Read Only Memory) chip, but that normally does not need to be replaced. It probably is more likely that something that is controlled by the ECM had an open circuit, or a shorted control solenoid.