Hi Brain Trust,

I'm having a difficult time sorting out my car: I picked up an issue where spark on Cyl 2/3 is non existent.

Car is running Rotrex SC, MS3 Pro, Fab9 Coil on plug kit.

• Fab9 harness and coils are new - no change in behavior
• Traced the blk/white wire that runs to the stock coil harness - no shorts found
  • What's a little odd here is that wire has continuity at the plug between it and the ground with the key off? Is that normal?
• Cam sensor is new - no change
• Crank sensor removed, cleaned and replaced and known to work - no change
• confirmed all (I think) grounds
• In TunerStudio I can testmode the injectors and hear them firing, fuel pump works, when trying to test spark on 2/3 there's no noise unlike 1/4 where there's an audible click.

I'm still learning TunderStudio/Log Viewer so I don't have a lot of good data to share but if someone can guide me on what to look for/validate there maybe that's helpful?

Anyone have any ideas??

 

To confirm your second bullet, continuity between the trigger wires from the coil to the ecu connector? Is there continuity to ground with key in?

 

I think the trigger wires are the brown/ brown/yellow ones? Those I think are OK.
The continuity test was between the blk/white power wire and the ground wire.

Continuity not present with the key ON

 

I don't know what year car to tell you colors but i'd test continuity. You mentioned you think they are okay. It would be easier to confirm they are okay by checking continuity between both ends of the wire. One probe on the ignition coil connector side and another probe on the ecu connector side. If there isn't continuity between both ends of the trigger wire, you know your problem.

 

This. Also, while both ends are unplugged, confirm that the trigger wire is not grounded. Ecu triggers to ground to fire the coil, so if its showing any connection to ground (even with some resistance) with both ends of the looms unplugged, you've got a short to ground somewhere in the trigger wire.

 

Thanks for the pointers here....I haven't had as much time as I'd hoped. Did some quick checking on your feedback and have not found any glaring issues.
Picked up a new issue where trying to start the car turns over for a second then seems like its 180 out of time but it's not.
Battery seemed weak so it's on a charger and I haven't messed with it since.

If anyone else has any ideas, I'm all ears!

Also, if anyone is near the Bay Area and works for beer......c'mon down!!