How does the cooling system work

It really sounds like the thermostat is not opening to allow coolant to circulate that would explain the upper hose hot and the bottom hose cold.That is if you have not changed the coolant recently otherwise you could have air in the cooling system. let me find a guide for you.

Here is a guide for overheating let me know what you find:





https://www.2carpros.com/articles/engine-overheating-or-running-hot

My radiator fans are not kicking on at operating temperatures, fan and motor are working fine. when I pull the coolant temperature sensor plug fans kicks on but it is not kicks on when plugged at operating temperatures. And my radiator is also hot at upper end and thermostat for my car is at lower hose.

From the fan coming on when unplugging the temperature sensor but not coming on from warming up like before it heats that sounds like a bad coolant temperature sensor. You said the lower hose stayed cold when it got to operating temperature. That is why I was talking about a thermostat. But I also saw that you said it cooled down while moving. So the fan not operating correctly would make sense with that happening.

I changed the sensor today. Then I top off the coolant and was making sure by checking for the bubbles. I kind of see bubbles like three or four at a times and do not see them for a while and see them again (it was raining slightly assuming it is rain causing it bubble, correct me if I am wrong and educate me if it is head gasket related issue) after I changed the sensor and ran car in the first engine was creeping hot my fans kick on for a while still engines over heating so I shut it off. I ran the car again then it creeped little over operating temperatures and come down again then it never creeped up again until now. Need explanation why it creeped hot in the case if you can please. Other than that everything seems fine now but I will be checking it for a week before I ignore it. Thanks for your help.

It did not work. after running it for an hour it is overheating again.

So are both upper and lower radiator hoses getting too hot to hold? You would need to rent a chemical block tester from Autozone to see if there was exhaust gasses entering the cooling system. They will make you buy the fluid for the tester.

That means it is a head gasket? Oh no, I just bought this car.

Are both the upper and lower radiator hoses getting too hot to hold at normal operating temp?That's why your doing the chemical block tester to see if there is exhaust gasses in the cooling system.

It's not Everytime only sometimes I will say 1 day every 10 days. Today it didn't happen. And it didn't over heat too

So one day out of every 10 the hoses are too hot to hold and that's when it doesn't overheat?

I don't know today hose is hot and it's over heating it's creeps high fast if heat is on. Raditor fan not kicking on by itself again. I unplug the sensor fans turning plugged in reached almost to red but fan didn't kick on

I would run a chemical block tester on it.

If I have a head gasket problems or exhaust leaking into cooling system fans won't kick on ?

The fan should kick on but you also said both upper and lower hose aren't always getting too hot to hold.So it crazy how so many issues you seem to have.I would replace the thermostat since you said that both upper and lower radiator hoses aren't getting too hot to hold at operating temp.

Upper getting hot lower not getting hot until I drive like 50 miles

Yeah I would replace that thermostat

I will do that tomorrow

Sounds good

I replaced thermostat even the old one still looks good. Flushed the coolant. Yesterday it seemed fine that fan were turning on automatically and shutting off. But this morning its was foggy snowing and while I was car indicator creeping up since I have an obd scanner I checked the coolant temp it was about 195 F I pulled over checked for fans. There were dead and not coming on. indicator reached all the up obd sensor reading 195 F. Is 195 F is the ultimate temp or my sensor bad again because its a new one

195 isn't overheating thats about where most thermostats open.which engine do you have the 2.4L or 2.7L engine?

2.4 L 4 cyclinders. Actually I did a little experiment just now. I pulled sensor harness and plugged to my old sensor and put a light at the end of the. Since I have obd scanner I am watching temp while I am doing it the fans kick on 205 F. The problem is the indicator reached high on red at 199 F. And yesterday the we're kicked on at 170 F. I am really confused thinking to swap the sensor with new one again.

205 is probably the low speed fan 177 is too cold to have the cooling fan come on.

Iam sorry 170 is too low for the fan to come on.

What does it mean then? Something electrical

I found a sensor labeled water temperature but not sure if it's the gauge sensor.To me it sounds like the gauge is miss reading the actual temp if it doesn't match the new coolant temp sensor readings on your code reader.

Which car is that? Anyway I swapped it with duralast couple of hours ago. Now even 195 F is fall under operating temps. But fans not coming on. It went to 205F at one point still no fan. But it's not fluctuating like before

The fans are going to come on at like 210 on low then ramp up a little higher temp.Iam having trouble finding info on when the fans come on.That diagram is supposed to be your car.

But my sensor is under the hood. Yeah even I have trouble finding info on temperatures but I saw other Hyundai car which is from India it turn on in between 96C to 100C

100 Celsius is 212 fren which sounds about right

Again 212 is almost red on my guage

Take a picture of your gauge and post it please.212 isn't really that hot especially when most thermostats don't open till almost 200.that doesn't sound right that 212 is almost in the red.

Sure I will. Now I am not driving

Ok sounds good

So I have been using my obd scanner as my temp gauge it's been 2 days since I have changed temp sensor. And temp is not going beyond 207 it went to 207 only once most of the time it reaches to 203 and
I saw the fans kicking on automatically at 207 F. Indicator acting up a little but not going all the high to H. Assuming new temp sensor fixed the problem somehow. Still not confident enough. I want to do for a week and see if it's really good. I may contact u later.

Alright keep me posted