Our '96 Caddy STS is giving us some frustration. At times, the engine appears to hesitate, and then the gas peddle will lock. The message on the dash is 'emmissions 104', and then sometimes the 'check engine' light will come on, and sometimes we even have to pull over because it actually stalls. Usually after it sits over night, all is well. I've changed the plugs , air filter etc, but hasn't seem to have helped. Any ideas?
You need to take the car to a service center (not Cadillac) and have them check the diagnostic codes telling you something is wrong with the emission/computer system. The check engine light will go out, but leaves a diagnostic code. This will explain your running issues.