dhauzer

Hello,

The coolant gauge does not show constant value. It goes back and forth between 210 and 240. I replaced the thermostat with a new one. I think the coolant sensor is faulty.
I'm trying to buy another one, but I can't find the right one. The one I'm using now is in the picture. This has a different pin than what is required based on the catalog query.

XJ '87
2.5i 4x4 (AMC 150)

I can't find this part anywhere. I don't know what to put in it instead.

cruiser54

Make sure you're searching for a coolant temp SENDER or SENDING UNIT. Not a coolant switch or sensor.

Here ya go: https://www.quadratec.com/products/55109_0008.htm

lawsoncl

Between 210 and 240 once warmed up, or all the time? Stick a meter on it and drop it in a pan of boiling water. They typically don't get unstable, but rather just stop working. You sure you're it's not reading correctly? If you're losing pressure, then it may be reading right if it's intermittently seeing steam instead of boiling water. Still got that crappy surge tank with the fail-prone cap? I think it's a Volvo 740 cap that fits and is much better quality than the usual aftermarket caps that tend to pop loose.

I've never found an after market sensor with the spade connector, just the ones with the threaded top. You can change the wire to a small ring terminal and use a nut, or I think a female bullet connector will push on the threads too.