AC noise

Hi, I have an 01 GT, its still completely stock. Whenever I turn on my AC, I'll hear a knock sound. It's just a single knock and I only hear it whenever I turn it on. What could this be? Everything seems to be working fine so I just wanna make sure it's nothing major. Also, when I leave the air blowing without AC on the coldest setting, it blows warm air, not hot but a little warm. Are there any adjustment's I can make to the car to let it blow outside temperature air? Thanks in advance.
 
pt123 said:
Hi, I have an 01 GT, its still completely stock. Whenever I turn on my AC, I'll hear a knock sound. It's just a single knock and I only hear it whenever I turn it on. What could this be? Everything seems to be working fine so I just wanna make sure it's nothing major. Also, when I leave the air blowing without AC on the coldest setting, it blows warm air, not hot but a little warm. Are there any adjustment's I can make to the car to let it blow outside temperature air? Thanks in advance.

The clunk is the clutch on the AC compressor and it's normal to hear it when you turn on the AC.
 
It's either what Black_Cobra said or it may be when you change the switch from "vent" (pulling outside air) to "MAX A/C" (cycling inside air), what you are hearing is the vents closing. But if you are not getting real cold air the vent may not be closing completely for some reason (like a possum living in your vents). Alternatively, if you are changing the switch from "OFF" (vents closed) to "NORMAL A/C" (vents opened), you may be hearing the vents opening.

If it's a really hot day and your A/C is set to NORMAL, the air may not be that cool. But if it's set to MAX, it should be real cold no matter how hot it is outside.

But that's all speculation... :shrug:

pt123 said:
Are there any adjustment's I can make to the car to let it blow outside temperature air? Thanks in advance.

This may be a dumb question but is your thermostat set to the coldest setting? That's the dial with the blue/red ring around the knob. Coldest would be completely counter-clockwise.
 
Thanks for all the replies, it helps to know that it's nothing major. like I said, it doesn't really bother me but I wouldn't want it to become a big problem. GDawg, I do have the thermostat set on cold. Let me rephrase that last part. I meant to say that when the A/C is off and I have it set on the coldest setting, the air that comes in blows a little warm. The A/C blows very cold very fast so that's good but without A/C, its a little warm.
 
My car does that too. I think the air is drawn from the area below the wipers, between the fire wall and engine bay. It's a little warmer than the outside air, I think you'll have to learn to live with it like that. :shrug:
 
if you start hearing clanking and squeeking when the a/c is turned off and its coming from the motor. normally thats when the compressor clutch is/has gone bad, generally that sound it goes away when the AC is turned on. thats when you should worry. that isnt the case this time

the bump is like everyone has said is nothing to worry about, the is a/c kicking on when that happens.