Temperature gauge oddness

[RobH]

I've had a few coolant loss issues recently (pershed hoses, cracked bleed rail, broken bolt in thermostat housing)
All seems sorted now, minor weeping but bled and full now.
Over the weekend we've been away and initially, gauge rose to just below half way normally, however on the drive from Kent to Hampshire the gauge was rising and dropping at will with no relation to what I would expect the engine temp to be.

Heater still worked ok and when stuck in traffic the rad fan came on so assuming that's OK, again maybe a little drip loss of coolant but not significant.

Is there just a single temperature sender in the thermostat housing body, would it be worth replacing that to see if it resolves the issue or would you be looking elsewhere first?

[tforturton]

Sounds like you've got some air left in the system.

[CovKid]

Yes it does. You also may find you have to keep topping up expansion bottle for a while but give it another bleed.