A point to check is that the heaters in the lambda sensors have 12 volt power. Feed comes from the fuel pump relay so the voltage is only there when the engine is running. The fuel pump relay should be a single pole normally open relay, there are two output pins, the pump is wired to one pin and the lambda sensor heater to the other pin. If the wrong relay, such as a change over, is fitted the heaters will work when the engine is stopped, and turn off when the engine runs. ECU goes to limp mode and tends to be unhappy at idle. Found this fault on a Plus 8 where the service guys had changed the fuel pump relay.

A strange thing happened today. I replaced the cap on the top of the radiator as I kept seeing traces of coolant.
When I warmed the car up till the fan cut in, the temp gauge was registering about 15 degrees hotter than before. Maybe 100 whereas it was 85-90 max before.
I took it for a short run and it didn’t stall once. I don’t want to shout hallelujah but could there be a connection?

I know I haven’t fully tested it and it may cut out next time I take it out but I do feel a small victory.

I'm struggling to see the connection but stranger things have happened in a Morgan, enjoy the small victory.

Having walked round the park and had a look at the GoMog link I was given, the only connection I can make is that the coolant sensor is now registering as fully warmed up, whereas before it may not have been.
Traces of coolant was a bit of an understatement. I saw it bubble and squirt coolant out, but the rise in temperature came as a bit of a surprise.

Phil, by getting a better seal it allows the proper pressure in the cooling system, this allows water to reach a higher temp before boiling and producing micro bubbles (so you get better heat transfer)

Yes, that is my thinking that the coolant temp sensor have been previously confused by the low temp, but now it registers the correct working temperature.
It is speculation but if all the ECU sensors agree, then possibly it allows the car to tick over without unnecessary correction.

It does however, still occasionally stall until working temperature is reached, then it appears to settle down.
A decent run will confirm or not.

Nojoy.
Back to hunting and stalling.
Can anyone please tell me what and where a Road Speed Sensor is?

Mentioned as a possible cause in GoMog.
Thanks

Mine has a small box on the bulkhead where the two speedo cables join. It also has connections to the ecu. Bit of a fiddle to remove and open (its not supposed to be opened). Inside theres an inductive rotor that obviously sends info about the cars speed to the ecu.

I had some problems with mine (it was squeaking loudly) so I disconnected it and the idle speed increased.

As they are made from unobtanium I decided to carefully open it up and clean it out. It was full of white powdery corrosion and once cleaned and reassembled has worked perfectly and the squeak has gone.

this was the inside of mine

Many thanks
Unfortunately mine does not appear to have a mechanical speedo cable.