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.

[GregAmy]

Anyone with D-Jet that has not replaced the diaphragm should do so.

50 years later this is a service item, like replacing the cam belts on OHC engines. It's known to be hard to detect, and causes insidous and hard-to-detect problems.

In my own example, the car was starting and running poorly and I spent hours trying to diagnose it. Chris' shop suggested it was the diaphragm so I had Chris rebuild the MPS and FRICKEN VOILA! the car drove like a champ.

Seriously, if yours has an unknown history and/or is older than 25 years or so, just replace it.