A/C not working properly?

KASEYD

MEMBER
2004 FORD MUSTANG
200,000 MILES

When I drive, on highway my air conditioner will work fine. When I drive low speed as in town it’s like steam comes up (kind of like when the radiator overheats) but it’s on the passenger side towards the back underneath the hood. It stops immediately when I turn the ac off. Please help I have had this ac fixed 4 times and no one has been able to make it work more than a day or two.

1 Reply

AL514

MECHANIC
4,120 POSTS

Hello. What size engine is in your vehicle? First open the hood while the vehicle is running with the A/C turned on high and see if the A/C compressor is engaged and spinning or not. There is a clutch on the front of the compressor, you will notice if it is spinning or not.
In the picture below the arrow is pointing to the compressor's clutch. If the compressor is engaged that section will be spinning with the pulley, If the compressor is not engaged it will remain stationary and the pulley will just spin on the outside of the clutch. Let us know if that section comes on or not. It should cycle on and off about every 8 seconds or so. Check that first and post the results here and we will go from there.
If it's low on refrigerant it will sometimes run all the time without cycling, or not run at all if the pressure is too low. But we need to know if the compressor is coming on or not.

https://www.2carpros.com/articles/how-a-car-air-conditioner-works

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