I have a 1990 Honda Prelude Si with a B21A1 engine. I recently had the engine light come on and it is showing 9 flashes, or the Cylinder Position Sensor. I have checked the resistance of the sensor and it came back within specs, according to the Factory Service Manual. I have run all diagnostic procedures according to the FSM, checking resistance of the sensor directly at the sensor and at the end of the wiring at the ECU, all checked out within specs. I have tried a different sensor and also a different ECU, and the CEL is still coming up. I have checked to make sure that the crank to cam timing is set correctly. The engine was recently rebuilt and all was running fine, the only work I had done right before the light came on was replaced the alternator. I got my hands on a test harness and found that there is continuity when checking the wiring at the ecu test harness like the manual say, now my issue is a ran new wiring and the continuity and problems are still there. Why do I still have continuity at the body when testing at the harness and not at the sensor itself. This tells me it should be wiring but I replaced both wires and now change. Thank you for anyone who can help me.
have the same problem?
Friday, June 13th, 2014 AT 9:14 PM