Overheating Part 2

[Electric Banana]

Afternoon once again. Here's the scoop. After replacing the thermostat, radiator cap, and multiple burping I thought the overheating was beat. I the last week I have found that the Electric Lemon has started to run a little warm. The temp will rise near 240 and then drop to normal (210) and the repeat. Still not a blown head gasket. Checked and did not find any air in the system. I have found that the cooling fan is now runnng at full speed. I've checked for codes and only finding a code for possible bad gas cap. Now my question is, Can a bad coolant temp sensor be causing the fan speed and the continuous fluctuation in the water temps? Heater is working fine.

 

[Mopar]

Maybe on the coolant temp sensor. Put a new one in it and see.

What outside temps are you now running in? It’s crazy but 240 is the upper end of where the 3.6 will run under normal conditions.

Turn on the AC on low (your AC works right?) and drive around. Does your temps run lower and more stable? Turning the AC on forces the fan to come on.


Get JScan and the proper adapter to work with your phone. Use JScan to turn the fan on. Does the temp fall and stay low?

Get a laser thermometer (as already recommended) and check the upper and lower portions of the radiator. Is there a big difference in temps? What is the difference? The JK radiator having the return to the engine where it is does encourage deposits to drop to the bottom of the radiator which eventually leads to clogging of the radiator if you neglect your cooling system. Good chance on the earlier models of the 3.6 but lower chance on later models unless someone has mixed coolants.