[Dave Colangelo]

I had a no spark issue with my 924S (early 944 motor) when I first got it. It turned out that the ECU was bad. The transistor that pulsed the ground for the coil had toasted. I had the ECU rebuilt by some place and every thing was fine after that. I spoke with them and they said it was a common problem with these ECU's. Any way the only way to really check the coil connections is with an oscilloscope, you should see a square wave.

Not tightening the bolts on the sensors could prevent them from working. Not sure how much play is in those sensors as I have never replaced them. If they are lose in there and not at the proper angle to the sensor wheels they will not function correctly. From an electro-mechanical stand point they are designed to be a specific distance from the sensor wheels, if that distance is drastically off it will prevent the magnetic fields from affecting the sensor correctly and thus generating a signal.

Regards
Dave