It was only the 4th piston, but now the 3rd and 4th pistons are not firing.
-This is what I have done
-Pulled out spark wires to see what cylinders make a change in the engine i can pull out 3rd and 4th and the engine reacts the same, if I remove 1 or 2 wires the engine almost stalls.
-Checked for spark, all 4 cylinders and I have spark coming out of the spark plugs
-Changed distributor cap and rotor any way cause it was about time
-Checked compression and, 155 across
-Changed fuel rail because fuel injectors where leaking before, due to broken pintel caps (before and after the change 3rd and 4th still would not fire)( also after I swapped a known working injector into 4th just to make sure, and still no gas spray)
-Checked power wire to injectors all 4 have power.
-Checked wire going to the ecu from the injector all four has power (12v) all the way up to the ecu
Put a tester light onto the 1st injector (while running) onto the two injector wires and the light flickered
-Put a tester light onto the 4th injector (while running) onto the two injector wires and the light did not come on
-Checked my wide band car runs fully lean.
Decided to take a wire and put it from the 4th injector on the ecu side to the injector it self and nothing changed.
-If I put ground to the 4th cylinder on the ecu side the car runs fully rich.
Sanded down and cleaned any grounds that I could find, that was about 6 in the engine bay.
Changed the ecu to one I had in my garage car wouldn’t start, ( not sure if that ecu worked) had another ecu which is from an automatic ka24de which I’m pretty sure works and still the 3rd and 4th cylinder will not work.
Sooooo wtf.
IIRC the only wires going from injectors to the ECU are the signal wires which shouldn’t have a +12V reading, was it the signal wire you were measuring?
Measure the signal wire from the ECU to the injector with the injector unplugged and the ignition on in to see if it has power (if injector is plugged in it will read +12V). It sounds like maybe it has shorted to a power wire which is causing it to not fire and/or burn out the cyl 3 & 4 injector circuits in the ECU.
I had a similar problem a while ago, sometimes acouple of the injectors would get stuck open, other times they wouldnt fire at all. Traced it back to the ECU, opened it up and found this
Well I don’t know what to tell you guys, I put in new spark plugs, put my old distributer and ignition rotor back on, made sure the injectors where in completely straight when putting them back in (also removed that retarded tab on the back on the injector rail that goes on that stud, to makes things easier to install) and while the spark plugs where out I let the engine air itself out. And now it’s running on all 4. I’m not sure what made it work because I did it all at once. It’s still running really rich but at least it’s running on all 4 right now. Sooo I’m happy got some more work to do but 4 is better than 2. I’ll put the new cap and rotor on to see if that might have been the problem later when it’s not 12 am.
The test light at the injector still boggles me though …
After more figuring some more things out it turns out my ecu was the same as sidewayz240 's. The reason it wouldn’t run on the other A/T ecu was because the 3rd and 4th plugs where soaked in fuel. So in the end, I suppose it was the ecu, just remember to air out that engine before starting the car with a new ecu. That being said I need a New ecu, who is selling a good m/t one?
p.s Thank you to those who took the time to help me out.
