Hi all, I have S4 T2 with an old haltech E6x and the 13bt. I've been back home in NZ and trying to get the car back road legal and have run into a problem with the leading coils. The car was only running on the trailing coils and I thought it might have been the msd 6a I had installed so I pulled it out, and that didn't fix the problem. So I sourced another set of coils and hey, I had spark. All was going well and I took it for its check and once the guy hopped in to start the check it wouldn't start properly ( it failed it's test on some rust issues) and I drove it home and once again I don't have spark on the leading coils. I've checked and added more grounds, checked the cas, and checked the ohms on the coil and all seem fine and within spec.
So yea, I did about 30 mins running time on the new coils with approx 20mins of actual driving and had no issues and then bam, they stopped again. Anyone have any ideas?

 

its a pretty simple circuit, so there are two wires to the coil, one should have 12v power with the key on and the other is the signal from the ecu
so get it to do it again, and see if the coil gets power, and then step 2 is to check the wire back to the ecu

 

Thanks for the reply. Everything seems to be ok, we took it to an auto electrician who said we were getting ECU signal and have +12 but somehow we killed the coil.

Currently wiring up a set of trailing coils to run sequential ignition as I had a spare set that I tested and are good.

Question for any that know, there's a black wire that also comes off the leading coils, does that goto ground?

 

After a bit of research ( should have looked before asking) it turns out it's diagnostic plug. I ran it to ground which maybe why the coils stopped. Live and learn I guess