SR wiring issues...

[RaceBredHardbody]

OK, heres the run down, this isn't my first SR swap, I haven't ever had an issue like this before, but I have checked everything that I know. Everything is working, but I am not getting spark. I have tried 2 different ecu's, and 4 different Q45 ignitors. I can pull the CAS, spin it, and hear the fuel pump cut on, and each injector click, still no spark. Now checking the power on each coil, and the ignitor, E on each coil is always grounded, + on each coil has power when car is on, and the - on the coil doesn't show a full 12 volt ground ever, but it does seem like it fluctuates when trying to crank the car. With the car off, there is ground on the - pin on the coil all the way to the 5 pin plug on the ignitor, though to the other side, and to the ECU. I tested a buddies SR swap that I had done, and had the same exact signals on both swaps. Any ideas? Could the CAS be bad, it trigger the injectors, what else am I missing, I am sure it is something simple.

It's a S13 Redtop into a 92 auto coupe btw, converted to manual. The dash harness isn't connected yet, but that shouldn't cause this problem, right?

[bruinbear714]

Wow, what a headache reading through all that.

SR20 wiring guide to solve all your problems.

OK, heres the run down, this isn't my first SR swap, I haven't ever had an issue like this before, but I have checked everything that I know. Everything is working, but I am not getting spark. I have tried 2 different ecu's, and 4 different Q45 ignitors. I can pull the CAS, spin it, and hear the fuel pump cut on, and each injector click, still no spark. Now checking the power on each coil, and the ignitor, E on each coil is always grounded, + on each coil has power when car is on, and the - on the coil doesn't show a full 12 volt ground ever, but it does seem like it fluctuates when trying to crank the car. With the car off, there is ground on the - pin on the coil all the way to the 5 pin plug on the ignitor, though to the other side, and to the ECU. I tested a buddies SR swap that I had done, and had the same exact signals on both swaps. Any ideas? Could the CAS be bad, it trigger the injectors, what else am I missing, I am sure it is something simple.

It's a S13 Redtop into a 92 auto coupe btw, converted to manual. The dash harness isn't connected yet, but that shouldn't cause this problem, right?

[Hijacker]

I wouldn't totally rule out CAS, but I would first go through and double check your grounds. Primarily make sure there aren't any broken ground wires in the harness if you can. A lot of times, these issues come back to a simple bad ground.

Also, double check that your power lead for the coils is connected right. The coils should get a direct power source from the big connector located next to the battery.

If you have an extra CAS (which having that many extra ECUs and ignitors, I assume you do), it wouldn't hurt to try another one.

[RaceBredHardbody]

The brown and gray plug wiring is fine, I used Heavy Throttle's wiring like usual, and this is the first swap I have ever had an issue like this with, I am not a wiring genius, but matching colors, checking for powers and grounds is easy. I don't have a spare CAS, but is it possible for the CAS to fire the injectors and not the coils? I am getting another CAS this weekend to try, other than that, the only thing I can think of is a grounding issue, not missing any, they all seem to be there, and showing a good signal.

[Hijacker]

The ECU defualts to sumiltaneous port injection for startup, so you'll get fuel from the injectors if your car isn't running. It doesn't switch to multi-port until the car is running.

Try the othe rCAS for now and see if that remedies the issue. It's the only thing I can think of aside from grounds.

[bruinbear714]

Yes, its possible for the CAS to work properly without firing the coils. You can test each coil by putting a philips into where the spark plug goes and placing it next to a ground. You should see arcs as you crank the engine. If you don't, then either:

1) Your CAS is bad.2) Your ignitor is bad.3) Your ignitor/coil harness is bad.4) Or a combination of the three.

The brown and gray plug wiring is fine, I used Heavy Throttle's wiring like usual, and this is the first swap I have ever had an issue like this with, I am not a wiring genius, but matching colors, checking for powers and grounds is easy. I don't have a spare CAS, but is it possible for the CAS to fire the injectors and not the coils? I am getting another CAS this weekend to try, other than that, the only thing I can think of is a grounding issue, not missing any, they all seem to be there, and showing a good signal.

[bgsr240]

I have exactly the same problem. I've checked and rechecked the grounds, connections, and the whole wiring in general. I even bought a brand new wiring harness... an S14 sr harness, by the way (NOT cheap) and tried my spare ignitor. The only thing left that can be causing problems is the ECU I guess.

[RaceBredHardbody]

Bruinbear714, I have check all of the coil that way, thats how I know there is no spark. I guess I will try a CAS this weekend, hopefully that works.

[RaceBredHardbody]

CAS is good, checked it on another running car. I double checked all of the wiring, to FRSports website, and Heavy Throttles, it is all the same. I had another SR swapped car I double checked all of the signals on, and they are all the same, can anyone think of anything that I might be missing, or overlooking? It's gotta be something simple. I have double checked all of my grounds. Any ideas?

Thanks

[Hijacker]

It's gotta be either a ground issue or a power issue. At this point, I can only suggest running continuity checks. You've ruled out faulty everything else, now you only have the harness to look at.

[RaceBredHardbody]

Bad coil pack harness.