No Spark on my '85 - HElP
 

I have no spark on my '85 911. I have pulled plug and grounded against engine and nothing. I checked primary resistance (1-15) on coil and it is .6 ohms, secondary (15-4) is 5700 ohms. (These are in line with what I checked on my sons '87 944 (same coil) - I even swapped them out. I also have 12V into #15.

What next?

Thanks

Trey

DME relay, or engine speed sensor is my next guess

The DME relay is new, and the speed senson has good resistance (to spec). Any other ideas?

Do a search - this topic gets covered about every other week. First check if you get power to the DME with the key to ON (vibrating ICV), next check if you have +12 volts at the coil with the ignition to ON. If the sensors are good (oscilloscope) check if you get fuel injector pulses during cranking (LED test light). If no, sensors or DME are suspect, if yes you either have a bad coil, bad distributor or a bad DME.

Ingo

On my car it was the coil and or the coil wire. When you pulled off the coil wire, you could see it had burned trough.