weired one.u seem to have coverd all of it.I think u'r going to have get exotic on this one and start to assume a wireing fault.check for any chaffed insulation on the harness,and disconnect all block connectors and clean with electrical contact cleaner.i reassemble them with petroleum jelly.do the same to all earths not forgetting any that are close to the ecu.check all screening cable covers on the cas and cam sensors,it's possible they are picking up stray voltage signals.after this if still faulty try dissconnecting the alternator and see if that affects it.and now we come to the point of back probing the ecu with an oscillascope for live readings.steep hill to climb that one.
