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Jeep overheating, no heat, no air conditioning

Help! I have a 2011 Jeep Grand Cherokee with about 167,000 miles and I am having several issues. It all started when the thermostat was reading hot. First the coolant lines were flushed, that didn’t do anything. Then the radiator, water pump, thermostat and sensor were all replaced, the Jeep was still over heating. After bringing it to several different mechanics I had a few telling me head gasket and a few saying needs a new engine. So, I ended up purchasing an engine off a 2015 Jeep with about 50,000 miles and paid for an engine swap. The Jeep definitely ran better after the engine swap but the thermostat is still going over to the right and I only have heat on the lowest blower settings (and when it’s 40 degrees or warmer). Does anybody know what the issue could be!? I had someone say now it’s probably the heater core…thoughts on this? I feel there aren’t too many parts we can replace at this point.

Blocked heater core is possible. When the engine is hot and running, the two hoses on the firewall that go to and from the heater core should be pretty hot - about like the hose at the top of the radiator. That’s a sign that hot coolant is circulating everywhere it’s supposed to go.

On some cars there’s a valve, controlled by the HVAC cool-hot dial or slider, that controls the flow into the heater core. That valve, or its control, could be involved, if present on your car.

A blocked heater core won’t make the temp go up. Do your cooling fans run when the temp goes up. On most Chrysler products the gauge should read just above half way. Low coolant level can cause the symptoms you describe, either because there is air trapped in the cooling system or you have a leak.

If you have overheating at highway speeds, the cooling fans have nothing to do with it.

Anything over 60/65 mph is when the temp gauge goes up.

Check the radiator when the engine is cold, The coolant should be right up to the top. Did you put a new radiator cap of the right pressure on the new radiator? Any leak , no matter how small makes the coolant recovery system not work. Get the system pressure tested again. I hate to bring it up but it is possible that you have a bad head gasket.

I don’t like the sound of some mechanics thought you had a bad head gasket and others thought you needed a new engine. If a mechanic tells me it is the head gasket, I want to know exactly how he determined that and I don’t want to hear it is because we tried everything else.