Mitsubishi GTO/3000GT issues.

I am helping out a friend with his GTO and have had nothing but trouble.

Its injected but a 91 or 92 so I can't scan the ecu.

The car was blowing massive amounts of dark smoke, so the owner had the engine replaced with a secondhand replacement 6g72 TT (both engines gen 1)

The car was dropped off driving. He picked it up not running at all.

So far Ive swapped fuel pump and now have fuel to the rails (previously didn't). Have spark (previously didn't). Fresh gapped plugs fitted. Removed the alarm. It fires if I spray it with eth mix from a can. The injectors have power and none seem to run. Ive swapped the ecu out for a spare and it made no difference.

The car gets nothing on the tacho when turned over and has a combination cam and crank angle sensor (went to swap crank angle but found it was not a separate sensor). I have tried using another sensor with no change. Have tested most connectors for power and everything seems ok.

The timing is off from a visual check of the cam gears based on research.

One of the wires from the oil pressure switch and gauge unit connector. I'm unsure if this effects start up.

Please help me.

Based on the current situation Im guessing its ecu related or the timing being really out?

Any and all advise appreciated.

I think you would need to put an oscilloscope as the next step on the triggers to see what they are generating to the ecu. Without accurate engine position information the ecu won't ever tell the ignition or fuel injectors to fire. Obviously make sure the ecu power and ground are good and the engine grounding is also in a good state of repair (bare metal contact with clean surfaces).

If all that measures out ok, I would say it sounds ecu related and I would personally go to a stand alone rather than rely on 91-92 oem ecu at this point if you want real control. The early 90s cars are excellent candidates for stand alone engine management as most times the systems on the cars are segregated so the engine control doesn't have any complex integrations with the rest of the car.