1998 Lincoln Mark VIII V8 Two Wheel Drive Automatic 85000 miles
I have already done a lot of investication into the engine light on. I have comfirmed the 30 amp fuse and that there is 12v at the pump relay and vacume soliniod. The pump will work when 12v put to it. The pump will go on if I ground out the orange wire on the electronic relay. The vacume soliniod will open if I ground it also. My understanding is that the PCM must ground these items to make them come on. I have no schematics and the wiring is overwhelming. Is there and device between the PCM and these items that would stop the grounding of these devices. Any advice would be greatfull as I have come to a dead end. I have no other troubles with the car, but could it be a bad PCM? Or is it more likely a wiring problem?