I've done all the searching I could do, but I can't seem to find a satisfactory solution/answer. I have a 1987 RX7 with an NA 13b. I had problems getting the car to start for the longest time until recently. I traced the engine/body harness and repaired all the grounds I could find, and so with that I finally got the engine to start. But throughout all the testing for ignition/fuel/etc., my leading coil never put out a spark.
Right now it's only running on the trailing coil. I've done all I can think of. Sparks plugs are new with less than 100 miles on them, cables are brand new NGKs. I measured resistance on two different leading coils and results are good by repair manual specs. From what I have gathered(correct me if I'm wrong), both coils receive their signal to fire from the same source, so if that is true, the lead should be receiving it(???). I have measured voltage at the connector, one pin reads 12v, and the other 6v. I'm honestly not sure if this is correct, I've been told that the lower voltage pin is supposed to be a ground pulse or something, and that it doesn't have a constant current. Please help me figure this out, I'm pretty sure both coils aren't bad. Is there a ground I missed maybe? Anything is appreciated, thanks!

e-rod

 

just to clear up,The Leading COILS fire to the plugs at the same time.
Try cleaning up the body where the coil mounts so that it gets good contact to ground.Also Run a Wire from that point to the Negative on the Battery to establish a Good ground for the coil.

 

The Green/Yellow is the wire which alternates between 5 or so volts and then to zero. W/key to on and the Main Pulley rotated enough you should see the voltage change.

 

I sanded the surface underneath and even the metal underneath the body of the leading coilS, I thought that would be enough. Never thought of grounding it directly to the battery...but I guess it's worth a shot. More later..

 

If the voltage on the G/Y wire does not change as it should then it cannot be caused by a grounding problem at the coil. If the voltage does not change then it is not possible for the coil to work.

 

Didn't work.. So obviously the problem is not the ground. Could it be the CAS? ECU? Break in wire somewhere? I'm running so rich, and there's lots of smoke at higher RPMs.

 

Are we talking to ourselves here?

 

The voltage changes at the g/y wire. Still no spark.

 

Then the coil/igniter is bad especially if you are checking for spark at the coil bores. If you are not checking it this way then the plug wires/plugs could be the cause.