Help needed: Jeep suddenly overheating after changing the thermostat
- Thread starter dukesilver24
- Start date
JeepDawgHill
New Member
Thank you for the welcome and for the reply! I will have to ask about the coolant. Sorry if this is a dumb question...but what is the correct antifreeze?
Honestly a little depending on how he wants to do it just expect to have a full coolant flush when he changes it but it's under the driver fender on the block real easy once you get to it, also I can be corrected if wrong but its purple/violet coolant specifically for Chrysler as they started making the jeep engines.
JeepDawgHill
New Member
I think that's the sensor that was next on his list to check/change. It's my daily driver and he didn't have the time/part to do that today.
It will take him about an hour to change it from start to finish as I was able to do it at home with a socket set and some pliers. It's one of those parts that is easily overlooked.
JeepDawgHill
New Member
Good to know. I’ll have him go ahead and order the part! Thanks again for your knowledge!
I have a 2016 Unlimited JK and I have had my stat changed 3 times in 2 months. Dealers basically gave it back and said let us know if it causes the check engine light to come on again and we will replace it again. OEM stat is on backorder and not sure when they will get any inventory in. It's frustrating since I live in CO and climb around 3000 in elevation daily to go to work. I am really frustrated with this whole situation and no real answers. If you or anyone has any advise or what to do please let me know.
There is no such thing as an OEM Jeep thermostat. They just buy them, stick them in their box, and charge you for the name.
Most of these problems end up being a failure to properly burp the engine. Run the front end up on something. Ramps, jack stands, one of those concrete wheel stops in the parking lot... Just make sure the radiator cap is the highest point in the system. Pop the cap off the radiator (let it cool first, obviously). Start it up and let it idle. Turn the heater on hot, so the heater core gets burped. Top off the fluids. I keep doing this till it's stopped bubbling, and the fan has cycled 3-4 times (minimum).
The other common culprit is the fan. So the above procedure also ensures that it's actually cycling.
Most of these problems end up being a failure to properly burp the engine. Run the front end up on something. Ramps, jack stands, one of those concrete wheel stops in the parking lot... Just make sure the radiator cap is the highest point in the system. Pop the cap off the radiator (let it cool first, obviously). Start it up and let it idle. Turn the heater on hot, so the heater core gets burped. Top off the fluids. I keep doing this till it's stopped bubbling, and the fan has cycled 3-4 times (minimum).
The other common culprit is the fan. So the above procedure also ensures that it's actually cycling.
Thanks for this info. I will definitely try this and see if it fixes the issue.
Wow I've got a 2012 that I'm having heating issues with and I know that it's probably the fan do you know if they make aftermarket fans that are decent that workThis is gonna be long so hold on to ur shorts….
I experienced an under temp code so I changed the thermostat. (BTW anytime you put in a new thermostat, ALWAYS take it apart and work the action to ensure there is no factory gloss seal inhibiting it from opening on its virgin trial)
A week later I started getting overheating codes thrown. Tried several things to include new water pump, coolant flush etc… no bueno… was still getting super heated on the back side of the thermostat.
Had noticed a bit of oil in the coolant after the flush. Went back and looked at the coolant I had flushed out and there was oil in it as well. Checked the oil and thank the Lord above, no coolant in the oil. Did however find the valley between the heads full of oil and coolant mix.
Pulled everything down to heads and found slight seepage around 4 and 6 cylinders… bad juju.
Ended up pulling heads, which were warped and gaskets blown.
Milled heads put everything back together and still an overheat issue.
NOW FOR THE REAL ISSUE THAT CAUSED EVERYTHING TO CASCADE INTO MAJOR ISSUES:
The TCIP (computer mounted on the cooling fan) had malfunctioned well before the under heat issue. It was, unbeknownst to me, only running when the ac was on, thus overriding the tcip and coming on at low speed and quasi-cooling the engine.
Over a period of time, the engine was overheating somewhat on a daily basis… which later lead to the plastic oil cooler/filter housing in the valley to eventually crack and loose it’s seals, thus mixing oil and coolant on the coolant side.
This eventually led to a development of the heads overheating on a regular basis, which in turn led to warped heads and head gasket failure.
All is fixed now, but it was an expensive lesson learned about the JK 14 and later coolant fans.
IF YOU BEGIN EXPERIENCING OVERHEATING ON A 14 OR LATER JK:
Start the engine and get it to 225 degrees F. If the coolant fan does not kick in at precisely 225 F, replace the fan immediately. It will throw a code that does NOT set off the check engine light and will let you keep on driving with an ever increasing overheat issue that you simply don’t know about until catastrophic problems have already developed.
Hope my experience helps other JK’s 14+ out there
And yes, I replaced the oil cooler/filter housing with the aluminum Doreman housing to avoid the plastic sitting in the valley of heat death issue as well.
kevinhomuth
New Member
Most importantly you need to use the OEM thermostats. Chrysler has 54,000 on back order against their supplier so they are hard to find. I called around and found one about 2 hours away. Service manager told me the only 2 after market ones that they have had some success with has been the Dorman and Gates products. I had the Napa brand one and when I purchased the OEM one and put them next to each other it was shocking how much more flow the OEM one has. The Napa one had less than half the flow, I put pictures on my thread of the difference.