Hope this is the right category.

While driving one evening, I got the "check gages" notification. Looked at the gages, and the engine temperature was high. Pulled over to a parking lot, waited 2 minutes after filling air, and the temperature was back down. Started driving again and after about 5 minutes, got the high temperature again. Turned the car off, waited literally a minute and the temperature was not hot. Still over the middle of the gage but not in the red. Drove for about 20 minutes and no notification.

Any ideas what the issue might be? I'm thinking the coolant temperature sensor. I'll look for the part and try changing that. Anything else I should check or do, before the sensor?

Thank you


2002 Dodge Durango SLT Plus 4.7l

 

Did u check the coolant level in the radiator and overflow bottle?

 

I was perplexed with the so quick change in temperaure readings from high to not high, that I didn't think about that.
I checked it now, it wasn't bone dry but definitely low, right at the "Add" on the dipstick. Added some. I'll go for a test drive this evening and report back.

Thank you

 

Sounds like you just checked the overflow bottle. Remove the radiator cap as well (don't do this on a hot engine). Coolant should be up to the neck. Keep an eye on it even after u add it. You may have developed a leak somewhere. Usual places are hoses and worn out water pump.

 

So I open the marked cap, and fill in the reservoir until the fluid is up to the neck when the engine is cool and off?

Opened the cap, after it had cooled down. There was some pressure built into it. I could see the fluid but not up to the neck (will top it up after I get the response). Want to make sure that I understood it right.

Took it for a drive, and after about 10 minutes I could see the temperature gage getting almost to the upper end of the white part (just below too hot red). I pulled over and started the heat inside. Waited a minute and the temperature gage went to the middle. Drove about 10 more minutes and the gage needle pretty much stayed at or near the middle.
Not sure if the hear had anything to do with it or not.

I am thinking the possibility might be air in the system and I need to burp it? Or the coolant temperature sensor and maybe the thermostat.
Any suggestions what way should I proceed and check first?

Thank you

 

You burp it by jacking up the front or up on ramps (higher the better)and running it with the radiator cap off. Watch for air bubbles to stop and adding as needed. Turn heater temp to full hot when doing this. It can overheat for various reasons aside from low coolant. Bad cooling fan clutch, malfunctioning thermostat, failing water pump, large air pockets. Gotta figure out which it is.

 

I'll do a burp and report back.
Another thing I noticed is, as the engine temperature rises from the middle of the gage level to H, the oil pressure gage decreases. Does this help in any way to figure out the issue?