Hey Rover Forums, I'm just a little confused as to my symptoms here. I've had an Ultragauge showing engine temps for as long as I've owned my D1, and its always run between 172 - 182 depending on how hot or cold it is outside. I recently changed the valve cover gaskets and lost some coolant while disconnecting hoses, needing to refill about a gallon after the job was done. I did all this work at my parents house over the weekend and drove it home Sunday night. She ran at 176 degrees, the sweet spot. Next morning comes along and the Ultragauge won't read above 123 degrees at max. I still have heat and the engine temp dial reads right in the middle, which I heard can't reach that threshhold unless the engine is at least 140 degrees. It kind of bothers me, and I'm wondering if I just need a new thermostat.

 

could be a flakey Engine Coolant Temp sensor. There are two. One feeds the gauge on the dash and the other feeds the ECU. I suspect you will eventually have a P0116 code.

https://landroverforums.com/forum/di...bd-data-95276/

 

Good to know! I remember unplugging that thing when I was doing the valve cover gasket job. Must've ruined it somehow..