Temp and Fan Issue

Atlgurl9225

New Member
Joined
Dec 27, 2023
Messages
5
Location
Dacula, GA
Hello from Dacula, GA! Hope everyone had a happy holiday and is looking forward to a great new year.

I am a reasonably new jeep owner (Sept 23) and we love wheeling and upgrading her. It's a cult we're happy to have joined. 😂

I was wondering if anyone might be able to help me with something I've noticed lately. I am very capable of doing small jobs and light maintenance work but I don't want to start tearing into things because Dr. Google thinks it might be the answer.

My 2013 Sahara (the Pentastar 2.6, 100k miles) doesn't have any leaks or any obvious issues but here is what I'm trying to puzzle out. It will run hot (sort of) sometimes. It never quite gets to the 3/4 mark, but it gets close, and will stay there for a minute or two until the fans come on and bring it back down to the usual halfway. It's not at any particular time, though I did notice today when I hit the gas a bit harder it went up pretty quick (but came back down just as fast, within 30 seconds). Concurrently, the heat blows hot and cold sometimes, and I can kind of manipulate it by changing the heat setting dial. I can't pin it down to moving or idling. Also, when idling in the driveway it never gets hot, to the best of my knowledge. I just had the oil changed somewhere and they topped off fluids, etc (allegedly). I don't know if I would even notice that it is doing this at all unless I was constantly looking at the temp guage. I don't remember it doing this with the heat either, but I ride with the top open a lot and haven't really used the heat until now.

I can change the thermostat myself and will likely start there since it pretty easy. Based on what I experience, I think that might be a good jumping point. Has anyone else encountered this with their JK's?

Edited: on a whim, I checked the coolant reservoir. Trucks been off for maybe an hour, but still warm. I can just barely see coolant in the reservoir about an inch or two below min line. Should I just add coolant to the reservoir and see if that helps? Still don't think this would affect the temp inside the cabin. 🤔
 
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Hello from Dacula, GA! Hope everyone had a happy holiday and is looking forward to a great new year.

I am a reasonably new jeep owner (Sept 23) and we love wheeling and upgrading her. It's a cult we're happy to have joined. 😂

I was wondering if anyone might be able to help me with something I've noticed lately. I am very capable of doing small jobs and light maintenance work but I don't want to start tearing into things because Dr. Google thinks it might be the answer.

My 2013 Sahara (the Pentastar 2.6, 100k miles) doesn't have any leaks or any obvious issues but here is what I'm trying to puzzle out. It will run hot (sort of) sometimes. It never quite gets to the 3/4 mark, but it gets close, and will stay there for a minute or two until the fans come on and bring it back down to the usual halfway. It's not at any particular time, though I did notice today when I hit the gas a bit harder it went up pretty quick (but came back down just as fast, within 30 seconds). Concurrently, the heat blows hot and cold sometimes, and I can kind of manipulate it by changing the heat setting dial. I can't pin it down to moving or idling. Also, when idling in the driveway it never gets hot, to the best of my knowledge. I just had the oil changed somewhere and they topped off fluids, etc (allegedly). I don't know if I would even notice that it is doing this at all unless I was constantly looking at the temp guage. I don't remember it doing this with the heat either, but I ride with the top open a lot and haven't really used the heat until now.

I can change the thermostat myself and will likely start there since it pretty easy. Based on what I experience, I think that might be a good jumping point. Has anyone else encountered this with their JK's?


Air pockets are a common overheating problem with the cooling systems. Most People don't know how to properly burp the cooling system. It usually doesn't cost anything for someone to check that first.

Just raise the front of the Jeep up about 6" higher then the rear with the cap off and engine idling,
 
Air pockets are a common overheating problem with the cooling systems. Most People don't know how to properly burp the cooling system. It usually doesn't cost anything for someone to check that first.

Just raise the front of the Jeep up about 6" higher then the rear with the cap off and engine idling,
I will try this, thank you! My driveway is on an angle so that's pretty easy to accomplish. 😁
 
Hi, me again!

So I tried to do this and the problem didn't change. I ended up taking it to a jeep dealership who said the diagnostic was $213 and I left it this morning. I got a call back around noon saying the technician was requesting an additional hour to compression check it, as he was seeing bubbles in the radiator and suspects a head gasket failure. Now, here's the thing.

Apparently we're $200 in and don't know squat. To my mind, I shouldn't be paying anything if they can't tell me what's wrong in the agreed upon diagnostic time. But I digress....

I asked how much it would be after the additional hour and test and they said $569.

That is JUST for a diagnostic, that I assume will be waived if they perform the work. Has anyone else encountered this? I thought for sure that taking it to the dealership would be the best bet but I have never heard of anyone paying $569 just for a diagnostic. Am I crazy? That would potentially be half the repair price of the gasket, IF that is the case. I'm not sure what to do here. Anyone have something similar going on?
 
I got a call back around noon saying the technician was requesting an additional hour to compression check it, as he was seeing bubbles in the radiator and suspects a head gasket failure
A failed head gasket may not show up in a compression test but should in a leakdown test. Possibly they are doing both?
 
A failed head gasket may not show up in a compression test but should in a leakdown test. Possibly they are doing both?
He did not mention both. He only said compression. :::sigh:::

The thing that's making me crazy is that is runs GREAT except that I noticed it would run hot, and had the heat issue. I'm feeling like they're just trying to find something.

Maybe I'm wrong.
 
He did not mention both. He only said compression. :::sigh:::

The thing that's making me crazy is that is runs GREAT except that I noticed it would run hot, and had the heat issue. I'm feeling like they're just trying to find something.

Maybe I'm wrong.

If I remember correctly the cooling fan has 2 speeds is it going on high speed?
 
If I remember correctly the cooling fan has 2 speeds is it going on high speed?
It steps up in intensity, and reminds me of the way the JL's turbo cool and sound. Starts out quiet and gets a little more intense before it stops. I am reasonably certain the fans are functioning normally. It is only coming on when it should, when my temp exceeds the halfway mark and approaches 3/4 mark. When the fan come so, the temp comes back down to normal.

I'm going to try to get a video of it by putting my phone somewhere. It gets hot, then manages to cool itself within about 1-2 minutes. The needle fluctuates so fast.