We learn by trial and error! Had had an intermittent starting and running issue with my 73 2.0. One day fine and the next it would not start or stall on the road. Had it out on Friday, and it ran fine, and then after ten minutes of driving, it ran rough, and then stalled out and would not restart.

Smelled fuel, pulled a plug and it was fouled out with balck soot; checked the others and all the same. Replaced the plugs with fresh (always carry a set of spares and tool kit!), and limped home, still very rough running.

Narrowed the issue down to the Cold Sart Valve or the Cylinder Head Temp Sensor causing a way too rich condition... Checked the Cold Sart Valve; wasn't the problem. My other set of hands (Kevin!) is fiddling with the CHTS... and he says "Is this thing supposed to just pull out?" while holding the Sensor in his hand!

I think my answer was "OH, Shit"! So we had to make a tool (13mm deep well thin wall 3/8's drive socket, notched with a Dremel tool to allow the wire to feed through and out the side when installing the CHTS. Luckily, I also had a new Sensor, cause the original looked kinda beat up from flopping around in there for I don't know how long. Super glued the washer to the body of the new Sensor, and it screwed in like Buttah, baby!

Hit the key and all systems were go!!!

Apparently, the original Sensor had been installed w/o a washer and just a bit of blue thread lock (NOT by me!) Eventually, the threadlock failed and the sensor vibrated out of the hole... who would of thunk it??? Apparently it was getting a read sometimes but not all of the time, like when I hit a bump, and boy did that screw up the computer fuel control! RICH, RICH, RICH!!!

So if your symptoms are similar with a stock DJet system, there is a starting point to check.

Even having the sensor just loose will cause stalling, stubmles, and no-start conditions. L-jet, too. BTW, loctite on the threads is a no-no. Increases the chances of a bad electrical connection. The Cap'n

Thanks for posting on this. I have almost exactly the same symptoms that you've described.

Chris

Been there, done that. Had the exact same problem about a year ago. Mine was loose, but still in the head. Car ran okay cold, but way rich when warm, IIRC.