[GT_Chris]

I'm curious to know if anyone else has had the problem my 2021 GT (7,000 miles) is experiencing..

When traveling at Highway speeds and then accelerating at half throttle or more after only a few seconds the car rapidly begins to overheat. The first time it happened i actually received an overheat warning message and audio tone. The car cools down quickly after cruising without any additional acceleration. I dont live in a particularly hot area (Southern California) and it has been happening in 70 degree weather.

The car is at the dealership right now but they cant seem to diagnose it at this point. They are able to re-create the issue during a test drive but cant seem to figure it out in the shop, no codes or other clues. The thermostat is functioning properly, coolant is full, radiator fans kick in and there are no apparent leaks. Really baffling...

 

[1st K5]

Faulty thermostat?

 

[GT_Chris]

Faulty thermostat?

They told me that the thermostat is working while in the shop, that was my first guess too. The problem is only re-creatable while under load so its hard for them to test if the thermostat doesnt work while accelerating.

 

[KunoMochi]

Could it be a loose hose somewhere or perhaps a low level of coolant? Maybe have the coolant flushed and see if it helps.

 

[1st K5]

They told me that the thermostat is working while in the shop, that was my first guess too. The problem is only re-creatable while under load so its hard for them to test if the thermostat doesnt work while accelerating.

If all else is fine, I'd change the thermostat and see if the problem persists.

 

[GT_Chris]

Could it be a loose hose somewhere or perhaps a low level of coolant? Maybe have the coolant flushed and see if it helps.

Dealer found a loose electrical connector to the water pump that was causing the problem, the water pump wasnt flowing enough coolant apparently.. Took it on a few good rips on the highway and it doesnt seem to overheat anymore.

 

[1st K5]

How much did it overheat btw? Aluminum heads warp when too hot.

 

[KunoMochi]

Dealer found a loose electrical connector to the water pump that was causing the problem, the water pump wasnt flowing enough coolant apparently.. Took it on a few good rips on the highway and it doesnt seem to overheat anymore.

Nice, glad to see they found the source of the problem! And yeah, I would follow up and make certain the heads are still within tolerance. Should be alright as the temp warning limit should be set below the actual limit to prevent any long term damage.

 

[1st K5]

Or white smoke that has a "sweet" smell.

 

[Andrew72]

You can do that and go through it if you really want, but the manual indicates that the car will shutdown and/or enter safety mode before it let's itself get that hot...

 

[jsolo_sx2011]

Was this a sensor wire of some sort? I thought the water pumps on the 2.5T were mechanical?

 

[GT_Chris]

Dealer found a loose electrical connector to the water pump that was causing the problem, the water pump wasnt flowing enough coolant apparently.. Took it on a few good rips on the highway and it doesnt seem to overheat anymore.

Update: the car started the same overheating behavior again, its back at the dealership.. So far they have told me that ''this is a weird one" and they opened up a line of communication with Kia's engineers to try and find out why it is happening. I also noticed that when accelerating and upshifting into 4th gear the acceleration seems to drop off, feels like a slipping clutch and the car is struggling... Told the dealer about that problem too so hopefully they can fix it while they have the car...

 

[Bmill357]

I'm curious to know if anyone else has had the problem my 2021 GT (7,000 miles) is experiencing..

When traveling at Highway speeds and then accelerating at half throttle or more after only a few seconds the car rapidly begins to overheat. The first time it happened i actually received an overheat warning message and audio tone. The car cools down quickly after cruising without any additional acceleration. I dont live in a particularly hot area (Southern California) and it has been happening in 70 degree weather.

The car is at the dealership right now but they cant seem to diagnose it at this point. They are able to re-create the issue during a test drive but cant seem to figure it out in the shop, no codes or other clues. The thermostat is functioning properly, coolant is full, radiator fans kick in and there are no apparent leaks. Really baffling...

Check your lower radiator hose see if it's warm after the car is at the operating temp

I'm curious to know if anyone else has had the problem my 2021 GT (7,000 miles) is experiencing..

When traveling at Highway speeds and then accelerating at half throttle or more after only a few seconds the car rapidly begins to overheat. The first time it happened i actually received an overheat warning message and audio tone. The car cools down quickly after cruising without any additional acceleration. I dont live in a particularly hot area (Southern California) and it has been happening in 70 degree weather.

The car is at the dealership right now but they cant seem to diagnose it at this point. They are able to re-create the issue during a test drive but cant seem to figure it out in the shop, no codes or other clues. The thermostat is functioning properly, coolant is full, radiator fans kick in and there are no apparent leaks. Really baffling...

 

[Bmill357]

I'm curious to know if anyone else has had the problem my 2021 GT (7,000 miles) is experiencing..

When traveling at Highway speeds and then accelerating at half throttle or more after only a few seconds the car rapidly begins to overheat. The first time it happened i actually received an overheat warning message and audio tone. The car cools down quickly after cruising without any additional acceleration. I dont live in a particularly hot area (Southern California) and it has been happening in 70 degree weather.

The car is at the dealership right now but they cant seem to diagnose it at this point. They are able to re-create the issue during a test drive but cant seem to figure it out in the shop, no codes or other clues. The thermostat is functioning properly, coolant is full, radiator fans kick in and there are no apparent leaks. Really baffling...

Are your fans constantly running and is your lower radiator hose cool after engine reached operating temp that's what mine is doing I'm going to call the dealership in the morning

 

[GT_Chris]

Are your fans constantly running and is your lower radiator hose cool after engine reached operating temp that's what mine is doing I'm going to call the dealership in the morning

its still at the dealership and thats one of the things they are telling me they are going to check. My Radiator fans would kick on shortly after reaching operating temps and would stay on for the duration of my drive.

 

[Bmill357]

I'm curious to know if anyone else has had the problem my 2021 GT (7,000 miles) is experiencing..

When traveling at Highway speeds and then accelerating at half throttle or more after only a few seconds the car rapidly begins to overheat. The first time it happened i actually received an overheat warning message and audio tone. The car cools down quickly after cruising without any additional acceleration. I dont live in a particularly hot area (Southern California) and it has been happening in 70 degree weather.

The car is at the dealership right now but they cant seem to diagnose it at this point. They are able to re-create the issue during a test drive but cant seem to figure it out in the shop, no codes or other clues. The thermostat is functioning properly, coolant is full, radiator fans kick in and there are no apparent leaks. Really baffling...

its still at the dealership and thats one of the things they are telling me they are going to check. My Radiator fans would kick on shortly after reaching operating temps and would stay on for the duration of my drive.

I'm having the same issue and the lower radiator hose is cold

 

[1st K5]

Is this issue in the 1.6 or 2.5?

 

[Bmill357]

Is this issue in the 1.6 or 2.5?

2.5

 

[1st K5]

2.5

Will pay attention on mine to see.

 

[GT_Chris]

Is this issue in the 1.6 or 2.5?

The GT, 2.5T.