I have a new compressor, low pressure switch, flushed system and recharged to proper pressure.

The mystery is that when I first start the car, it works properly at any highway speed or at idle. After 15 minutes of driving though:

When the car is at idle, the air works properly, air is blowing ice cold.

When you take off however, the air gets warmer (quits blowing cold), until you slow down, and then it blows ice cold again.

It does the same whether the recirc button is pushed.

I am at a loss and cannot figure this out. Can anyone shed some light on this perhaps?

Thank you.

 

Check that the valve that controls coolant into the heater core has a good seal. If it does not close all the way, that means some hot coolant could be going into the heater core, and heating your cooled air. When you are at idle, the water pump is not moving enough hot coolant through that leak to over power your cooled air, but when you are driving, it is moving a lot more coolant through that leak.

I have never personally had this issue, but if I did, that part would be the first place to look. It sounds reasonable based on your described issue.

The part looks like this. Try manually closing it off and see if that solves the issue. If it does, the cable that controls it might need an adjustment, or the part needs to be replaced. Good luck!

 

It turns out the thermostat was bad. The temperature got too high causing the compressor to shut off. I replaced the thermostat and it was fixed!