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]

OK, a quick update on the richness / flooding / non starting.

Finally got the time to get back to the car. Decided to check the spark side of things to make sure it had a good strong spark to start with. As I'd added the 123 distributor I read it's best to add a 123 coil, so cleaned up all the contacts and fitted one.

Car fired up first time. Not a miracle as it can do that. Took it for a run - was running really well, smooth. Used the car over a couple of days. Running great. Decided to change the oil and filter as it was still contaminated with fuel. Ran the car some more. All good. Ran around this morning doing a few errands. Went to take the car out this evening... won't start. Completely flooded. Oil contaminated with fuel again. (IMG:style_emoticons/default/headbang.gif)

Pulled the injector wires - cranked the car over 5 or 6 times and eventually it fired, ran for a few seconds then died. Plugged the injectors back in, car started. Ran it around to get it hot, running a bit ruff, then left it ticking over. Tick-over was 1500rpm rather than 1000rpm. Smells very rich.

Tested the CHT sender... this was the reading.