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.

[Halfnelson]

I’m not sure if this is relevant but when it does flood, if I unplug the injectors, turn the engine over, after a few cranks it’ll fire up and run for a few seconds on the fuel already in the system, then die. If I plug in the injectors then it’ll fire up and run. However it’s flooded so badly that the oil now smells of fuel.

[ClayPerrine]

I’m not sure if this is relevant but when it does flood, if I unplug the injectors, turn the engine over, after a few cranks it’ll fire up and run for a few seconds on the fuel already in the system, then die. If I plug in the injectors then it’ll fire up and run. However it’s flooded so badly that the oil now smells of fuel.

That really sounds like the CHT is open circuiting. I would find a good CHT (not the junk aftermarket ones currently available) and replace it. It is approximately $25.00 US, so it is a cheap investment to try to fix it.

And change the oil soon.

Good luck!