D-jet masters question/help needed, very low idle/stall when motor is hot Options

[DRPHIL914]

I think this has been getting slowly worse but I dont really run the car for a long drives around here and its been cold too, but yesterday during a longer drive to a PCA event, on my way back having a lot of stop and go traffic after the motor had warmed up and reached full operational temperatures, my idle was dropping below normal , about 500-600, and after stopping for gas and sitting for about 10 minutes idle was normal (1000rpm)

Motor is 2056 with d-jet, with ignition 123 distributor.
fuel pressure is perfect, timing etc all good. all sensors were put in new when this motor was built 3-4 years ago. and i have always left the idle about 1100-1200 due to the fact that when it was fully hot it would come tdownt o 850-900 but never wanted to stall.

My thought is that the CHT is acting up and the resistance must be too high hot and now is sending a signal making it just like normal d-jet would get heat sink if a hot motor sat for a short time then wouldnt start. - is that a lean or rich condition that happens i cant remember but looking for your ideas thoughts here.

Phil