07 explorer over heating only when ac is on.

[Sethrok]

After about 45 minutes of driving with the AC on, my car begins to overheat. When I turn the AC off the temperature goes down. I replaced the fan clutch twice, the water pump, the thermostat twice, the coolant temperature sensor and thermostat housing. When I start my truck up in the morning I can hear the fan clutch engaged for a couple minutes. I am thinking that something isn’t telling the fan clutch to cycle? I don’t know if that even makes sense. Could it be possible to have two defective fan clutches out of the box? I am at my wits end please help me.

 

[94Eddie]

It could be an issue with the radiator not cooling effectively. The AC has a heat exchange radiator that sits in front of the engine coolant radiator. When running the AC it dumps heated air that gets sucked through the coolant radiator. Typically this isn't an issue unless the coolant radiator is partially clogged internally or maybe there is debris blocking air flow through the fins. Are you seeing a drop in coolant level?

 

[Sethrok]

It could be an issue with the radiator not cooling effectively. The AC has a heat exchange radiator that sits in front of the engine coolant radiator. When running the AC it dumps heated air that gets sucked through the coolant radiator. Typically this isn't an issue unless the coolant radiator is partially clogged internally or maybe there is debris blocking air flow through the fins. Are you seeing a drop in coolant level?

I haven’t noticed a drop in coolant level. Should I maybe flush the radiator?

 

[94Eddie]

First, I would check for debris and/or bent fins preventing airflow through the radiator. Leaves, bugs, pine needle, even a dead bird etc. can collect over time and reduce air flow enough affect cooling ability. Debris can even build up between the radiator and AC condenser. Radiators can plug from scale buildup inside them. This will take more than a flush. Some chemical would need to be used to dissolve the scale. Even then it might not work and installing a new radiator would be required.

Also, is your AC blowing as cold as it should? If it is charged up to spec, and isn't blowing cold, this would point to debris and/or bent radiator fins being the issue.

 

[Sethrok]

First, I would check for debris and/or bent fins preventing airflow through the radiator. Leaves, bugs, pine needle, even a dead bird etc. can collect over time and reduce air flow enough affect cooling ability. Debris can even build up between the radiator and AC condenser. Radiators can plug from scale buildup inside them. This will take more than a flush. Some chemical would need to be used to dissolve the scale. Even then it might not work and installing a new radiator would be required.

Also, is your AC blowing as cold as it should? If it is charged up to spec, and isn't blowing cold, this would point to debris and/or bent radiator fins being the issue.

I didn’t notice any debris when I checked, And I checked the charge and the charge is good. When I am moving it’s blowing cold but when I’m idling or sitting at a traffic light it’s starting to get a little warm

 

[94Eddie]

When it overheats what type of driving are you doing? Stop and ago or highway driving?

 

[Sethrok]

When it overheats what type of driving are you doing? Stop and ago or highway driving?

Stop and go

 

[94Eddie]

This would lead me toward the problem being with the fan clutch or its controls. Does the fan clutch engage when the AC is turned on at idle?