I've been having some trouble with my Civic with a persistent code 4: crankshaft position sensor. Changed the distributor, and I still get the code. I chased the wires up to the connector by the battery, and there was continuity between the sensor and there. I'm starting to wonder if the ECU is going bad. The symptoms are a constant Check Engine light, rev limits to 3500rpm, reduced power, occasional fluctuating idle, and often idling a little high (1100rpm). Any ideas?