Background:
I've been trying to find the source of my 92's troubles for a while (running poorly). I've already replaced the spark plugs, o2 sensor (cheap universal. have a wbo2 waiting to be installed) and fixed a few exhaust/vacuum leaks and have only seen minor improvements.
While poking around in the engine bay, I found that when the car was running and I unplugged the injector for the front cylinder... nothing happened. So the car's running on three cylinders. So I replaced the stock injectors w/ a set of freshly cleaned and flow tested 550cc rx7 injectors (high impedance).

Problem:
The car still runs rough. Tried pulling the electrical connectors for the injectors again and when I pull the one for the front cylinder... nothing changes again!!!

All the wires coming from the connector seem intact, but for whatever reason, the front cylinder's injector is not working.

Do I replace the wiring harness for the injectors? Am I missing something else? This is really bugging me, so if anyone can help me figure out what the crap is going on I'd really appreciate it!

 

Do you have power at the connector?

 

Yep, just tested it again w/ a little voltage tester and both connectors cause it to light up, so there's power at the connector.

So I guess it's not the wiring going to connector then... :/

Is there anything within tunerstudio that I can use to better diagnose what's wrong?

 

have you swapped injectors yet to make sure one will fire in that position?

 

I would think swapping out all of the injectors for the fresh 550's and still seeing the problem at the front cylinder would indicate it's not an issue w/ the injector(s). No?

 

unless you are incredibly unlucky and just happened to have a bad 550 that you put in the SAME position... unlikely, but weirder things have happened

 

Further poking around would indicate the coil on the front cylinder is what's messing up. (swapping coils is much easier than swapping injectors)

My car has burned through 2-3 coils now (very early adopter of the toyota COP setup), have other people had issues with this and/or have there been any major updates to the COP setup? Everything I've read seems to look the same as my current setup.