1990 Galant, no injector pulse
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.
