Hi, I have a 86 GN and today my father was driving it and he stated the car was running weird and the check engine light cam on. He got home and the car would not start but, 20 minutes later it started but, not running right, a little rough but, drivable. I connected the OBD scanner like I have done a million times on this car and I get no info or nothing at all. I tried another car I have and the scanner worked as it should. So, where to start diagnosing? The car has fuel pressure so, I?ll know that?s good. How do I get the OBD system back to working so I can diagnosis? Or maybe a bad ecu? I don?t know? Any thoughts?