Temperature Issues

After rotating my tires today I decided to check all my fluids. I had a shop change my oil less than 3k miles ago and assumed everything was topped off. I looked in my coolant bottle and it was dry.

My temperature hasn't been going above 210 degrees which is odd without any coolant right? So I added up to the full line and took my jeep around the block. During the drive the temperature reached 220 degrees. Has this happened to anyone else? I add coolant and the the engine runs hotter? How does this happen?

2010 xj 4.0L 4x4

bosco01xj said:

My temperature hasn't been going above 210 degrees which is odd without any coolant right? So I added up to the full line and took my jeep around the block. During the drive the temperature reached 220 degrees. Has this happened to anyone else? I add coolant and the the engine runs hotter? How does this happen?

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Make sure that there's no trapped air in the system, and as further preventative maintenance replace your thermostat and gasket; my recommendation would be for an OEM one with the check valve built in. From the way you're describing things, it may have failed in a more-closed rather than more-open position once there was sufficient coolant pressure against it again.

Check the overflow bottle for leaks. It's not common on late-model XJs that they crack, but has been known to happen. Ditto the hose that runs to it from the radiator.

While you're poking around the radiator cap, if it hasn't been replaced in while (or you don't know when it was), get a new one with the correct pressure rating.

Eyeball and feel the heater and radiator hoses for leaks as well as the radiator itself.

If there's no noise or weeping from the water pump, we'll go with the idea that it's good for now - but that doesn't mean it's necessarily fully-functional.