After recharging the A/C system the engine started running hot

EMMYSWEETS

MEMBER
2012 KIA SORENTO
2.4L
4 CYL
2WD
AUTOMATIC
260,000 MILES

A/C was running warm tried to recharge it, but that did not work. Within an hour of doing this the car's temperature ran hot. It's been 100 degrees in Atlanta all week plus I drive a lot of miles daily. I opened the hood and noticed the coolant reservoir was empty, so I filled it with coolant. After the car cooled down by letting it sit for approximately 1 hour. Now the A/C blows cold, but the temperature is still running hot. See no coolant leaks, fan runs, not leak on ground or on engine. The radiator was full of coolant and the reservoir stayed full. The heater runs hot and will quickly return temperature to normal. Could I have trapped air in the radiator or a clogged hose? Could it be thermostat or faulty temperature gauge? Should I run any system cleaner through the radiator?

1 Reply

JACOBANDNICKOLAS

MECHANIC
108,269 POSTS

Hi,

How quickly does the temperature reach hot? Also, how low was the coolant in the radiator? Also, the idea that the heater helps cool it leads me to think the radiator may need to be flushed. If the thermostat was the issue, the heater wouldn't help. Are the radiator fins physically clean? If not, take a garden hose and clean it off. If it isn't dirty, then I would try flushing the system. Since you will have it drained, replace the thermostat at the same time.

Here is a link that explains how to flush the system:

https://www.2carpros.com/articles/coolant-flush-and-refill-all-cars

Additionally, here is a link that explains how in general to replace a thermostat:

https://www.2carpros.com/articles/replace-thermostat

Let me know if this helps or if you have other questions.

Take care,

Joe