Djet running way too rich... Still! Options

[Halfnelson]

Had a previous thread starting in 2022 about my 73 1.7 standard D-Jet running way too rich and flooding to the point where it wouldn't start. It's been an ongoing issue. I've had a go. 2 garages have had a go. I'm at the point where I'm beginning to lose hope.

A recap. Bought the car 2021, had a problem with intermittent flooding. So far have:
Checked MPS - holding vacuum.
Replaced CHT sensor and tested. Working when flooded.
Replaced fuel pump and tested pressure.
Replaced all vacuum hoses and tested for leaks.
Valves set and rechecked.
New 123 distributor.
New injectors.

Each time I think I've cracked it and it runs and drives - sometimes for a month or so. Then I'll go to start it and it'll flood again to the point where it contaminates the oil. I feel like I've never managed to get to the bottom of the problem. Just keep replacing parts. Thinking maybe a return line that intermittently blocks? I'm kind of at a loss.

[emerygt350]

My point was, he could borrow my ECU.

[JamesM]

My point was, he could borrow my ECU.

If you want to rule it out they should be the same. I generally try and disrupt that connection as little as possible and in my experience ECU is usually the last thing to fail and the few i have seen with issues fail either not firing one of the injector banks or not powering the fuel pump. Intermittent over rich flood condition, my bets are MPS or CHT.

if the CHT wire losses continuity/gains infinite resistance the systems goes puke rich to the point of stalling.

If the MPS looses vacuum intermittently it goes WOT rich. I have seen this happen with diaphragm cracks that dont always show up with bench vacuum tests.