Hoping someone had an idea! According to Easy Auto Diagnostics I have 12 volts to the dark green/ orange stripe wire at the connector to the coil. I also have activation signal from sensors, but there is no spark with spark plug connected to high tension lead at the coil. About a year ago using the diagnostic procedure says that with 12 volts and an activation signal at that connector, than the coil must be bad. I replaced the coil and it started right up, but now with a new coil NO SPARK! It doesnt make sense.

 

PCM fires the coil by turning OFF the ground. A test light plugged into the coil connector should flash while cranking. (noid light works good too.)

 

Thanks for your reply, but when I said in the post that I had activation signals that was confirmed by flashing LED bulb tester while cranking engine. What I am dumb-founded about is that as a stated in the post, in the past the same test results concluded that the coil was bad and with a new one the truck started right. Now about a year later with the same test results indicating that I need a new coil, a new coil did not help. Maybe the PCM is reading the sensor signals and not grounding them? Maybe time for a new PCM?
Thanks

 

That green/orange wire is the ASD output from the PCM. It also feeds the injectors. If you put a test light across an injector connector, and it blinks when you crank, it’s probably not that wire. I guess it could be a problem with that same wire between the engine harness and the coil. The injectors would still work. That Green/orange wire to the coil comes off a 5 or 6 wire splice in the harness.

On my 95, 5.2, a gray wire from the PCM to the coil is the ignition coil driver. You can check continuity from both wires in the coil connector back to the pins on the PCM connector. You can also jam a sewing needle into the coil driver pin on the PCM connector and check the voltage with ignition on, and with the engine running.