Originally Posted by
bigblock427
Hi Josh,
OK, i understand. A constant signal is definitely wrong. So you you have to check if it is the right sensor and if sensor and camshaft flywheel fit togeher. If there is an offset, or if the sensor isn't working correct itself. No wonder that you get missfire, because the ecu doesn't know the cam position, which also means she doesn't know where the 1 piston is and that means the ignition is firing at wrong timing. You need to get a clean square wave signal from the camshaft sensor.
Regards
Markus
Markus,
The constant signal is coming from ECU... Not the sensor. It is the correct sensor for M113 engines and M113 camshaft gear. Nothing is wrong with the sensor. It is harness short or ECU problem. Which is why we are thinking fried resistor to pull voltage from 4.96V to <1V. That way the sensor voltage can overcome the ECU's signal.
ECU is firing correctly because Crank sensor is correct and working. TDC cylinder 1 is determined by crankshaft position sensor which is functioning perfect.
Look at "Service Manual, 9 - 348 , Diagnostics check 3"