Hello all & @Netish -
2001 MPI here overheating when stationary for 5 minutes.
I am having the same problem. Fan not cutting in.
Just overheats and pops the lid on the expansion tank.
Seems fine when running around the place.
Fan works fine when I unplug the sender.
What did you do to sort the temp sender problem?
I've drained the system and replaced thermostat with 82 degrees.
Cleaned all the muck and grime from around the sender unit water side in the thermostat housing. It was caked which may have not helped the sender heating up properly and initiating the fan.
Running with tap water in for a couple of days to check how it goes and will report back but I would love to know how to check a temp sender unit.
I am guessing checking its resistance with temperature but have no figures.
Any help would be very welcome.