Hi!

I've got a 1990 Galant with a 2,0L 4G63 with the EFI Multi.

I parked it in the garage on Sunday, and just a couple days later, it wouldn't start at all.
It just cranks, with no sign of firing, except with starter fluid.

Here's what I've diagnosed so far:


  • It cranks and starts with starter fluid, so spark and air is present, just missing fuel.
    It starts for a bit if I manually set power to the injectors to release the fuel pressure from the rail.
  • Fuel pump works, good pressure at the rail
  • Sounds like good compression
  • Crank sensor in the distributor works
  • Injectors are all tested and work individually, but doesn't seem to get any pulse from the ECU.
    They have +12V on pin 1, and the ECU grounds them with the NPN transistors. These seem to have proper ground, I opened and measured them. Unfortunately I don't have an oscilloscope to check the pulses.
  • Sensors like the MAF get power, but at 12,5V instead of 5V in the service manual? Weird.
  • Diagnostics code is constantly on, which reads ECU fault. This is my main concern.
  • ECU has both power and ground where it should
  • ECU looks completely fine
  • Check Engine Light is on, and does not shut off after 5 seconds as it should
  • MPI Relay has power and works as it should, checked continuity

I'm completely lost on what else to check, does anyone have any suggestions?
I might be able to get my hands on another ECU this weekend, I know a guy with Galant parts laying around.

Might also order some capacitors, as they could be the culprit.