EJ20G dead cylinder with good fuel, spark, and compression

[SomeOldHobo]

I swapped in an ej20g from a 96 wrx with 88xxx kms that sat for a few months, along with the ecu and tranny into my 94 t Legacy. I did all the necessary wiring for the ecu change along with the 4 to 2 ignition conversion. At idle the engine runs terribly, lots of shaking. There is a tapping sound from the right side of the motor but different from lifter ticking. All injectors are ticking and all have 12 volts. But when I unplug the injector on cylinder 2 nothing changes, the idle is the same, doesn't bog down anymore than it was.

So, I swapped the #2 injector with the one in cylinder 4 thinking if it was the injector, the problem would move with the injector, it did not. There was some left over fuel in the rail when I swapped them over.

I tested the spark and plug outside the motor, looked good. I am using some msd universal wires I made. (yes I have the right leads on the coil going to the correct cylinders.)

Compression was 140.

No misfire codes.

Also, I am using the 22t engine harness for the 20g with a few slight modifications. Which was just extending the wires to the temp sensors.

Help

[Legacy777]

If the problem did not move with the injector then I would suggest checking the wiring on that injector back to the ECU for continuity to make sure it's good. If that checks out it's possible the injector driver could be bad on the ECU. Any chance you have a spare ECU you could test out?

[SomeOldHobo]

If the problem did not move with the injector then I would suggest checking the wiring on that injector back to the ECU for continuity to make sure it's good. If that checks out it's possible the injector driver could be bad on the ECU. Any chance you have a spare ECU you could test out?

Wiring is good, had the injectors rebuilt, no change. Im just about to check to see if the coil pack is giving a strong enough spark.

[Legacy777]

Do you have a noid light or something similar you can check that the injectors are pulsing?

[RoughDiamond]

Really rough idle and sounds like it runs on 2 cylinders?

Just finished my 20G swap into my 91, and used the 95+ style crank sensor, and I had to swap the pins due to the polarity change. Cleared right up.