Hello and welcome to LZ :)
Best to ask over in the defender section of the forum you will get more help https://www.landyzone.co.uk/forum/defender-90-110-130.7/
Update on the issue of my p38.
I've managed to sort it myself.
I feel a bit embarrassed, I picked up the wrong obd11 cable and continued to try and sort the problem with the wrong cable.
I only realised my massive c*** *p when I suspected...
My Rangie is on the local news. Just looking through bbc news site and guess who's car takes pride of place in front of photo. Always park there when I go to town for my hair cut
https://www.bbc.co.uk/news/articles/cq5lyydlj4go
If it does it again i seem to recall that the pick up on the intank pump can go which would pull in air if the fuel was low as in going round a corner, but dropping the tank is a bit extreme just to check, wait and see what happens you could...
@roythebus Fuel Burning Heater, a webasto heater to warm up the coolant a lot quicker, you can preset them to come on before you go out to the motor :)