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Overheating

My wife’s car overheats when idling and when the A/C is on unless she drives over 60mph…any suggestions?

Is there a electric fan involved some how in this mix?

Yes, it looks like they are running but not when they are supposed to.

The Kia Optima uses electric cooling fans. For some reason these fans aren’t operating when at a stop and idling.

Tester

So it’s a sensor that is causing the fans not to run at the right time?

Can you clarify “they are running but not when they are supposed to”? Under what conditions is each running?

One fan should operate whenever the AC is engaged. It draws air to dissipate the compressed refrigerant heat from the evaporator. The other should operate only when the engine is heating up. One is operated by a relay engaged by the AC circuit, the other by a temp sensor.

If the engine is idling with the AC fan not functioning it may overheat even if the other is running. Conversely, if the AC fan is operating and the other not functioning the engine may overheat.

By the way, what year and how many miles?

So it’s a sensor that is causing the fans not to run at the right time?

That could be one cause. There may be others. At this point we only know"?" the fan(s) is not running when it should. Why is another question. It is usually cheaper to figure out exactly what is defective than just replacing parts until you get lucky.

I do not know when exactly yhe fans run, I haven’t been able to take a long look at it due to conflicting schedules. She had one of the guys she works with look at it

it is an 04 with 79k