Faulty thermostat? Video attached

Js90

Member
Joined
Mar 20, 2022
Messages
30
Location
Florida
No codes, no lights…just room temp air blowing from vents and temp needle creeping up. Luckily happened right before I pulled in my driveway. Turned the engine off and took this video. Faulty thermostat?

 
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Couple questions as the video doesn't show a lot of anything, sorry.
1. Is the fan kicking on high? If so, where is the temp gauge when that happens?
2. Is the temp gauge fluctuating or just continues to creep up?
3. What does the temp gauge do when driving and stopping? Cools down when on the move and creeping up while stopped?

Easy way to check for a bad t-stat:
* start the engine cold
* wrap your hand around the upper radiator hose
* you should begin to feel water flow and a little heat around 190-200 degrees or so.
* if this happens, your t-stat is fine. It is opening and coolant is flowing. The problem is elsewhere.
* if the t-stat does not open, you will not feel any water flow thru the hose and the engine will overheat.
 
Couple questions as the video doesn't show a lot of anything, sorry.
1. Is the fan kicking on high? If so, where is the temp gauge when that happens?
2. Is the temp gauge fluctuating or just continues to creep up?
3. What does the temp gauge do when driving and stopping? Cools down when on the move and creeping up while stopped?

Easy way to check for a bad t-stat:
* start the engine cold
* wrap your hand around the upper radiator hose
* you should begin to feel water flow and a little heat around 190-200 degrees or so.
* if this happens, your t-stat is fine. It is opening and coolant is flowing. The problem is elsewhere.
* if the t-stat does not open, you will not feel any water flow thru the hose and the engine will overheat.
I screenshot this so I have it for next time! Because let’s be real, there will be a next time lol. Good info to have! Thank you! Try to learn as much as I can while I go. Always new to a problem but research and know for next time. It seemed the fan wasn’t kicking on upon further investigation! Replaced the thermostat, still overheating, realized the fan wasn’t kicking on. Replaced last weekend and all has been well since! 🤞🏻
 
I have a crappy autozone brand 🙄 I read you need OEM. Replaced fan and the problem seems to be subsided for now, however next project need to get an oem thermostat just to be on the safe side!
No you don't. Jeep doesn't make thermostats. They buy them, same as you. Then they slap their name on them and charge you more. Get a reputable brand (I like Duralast) and you'll be fine.