AC noise

[Chris10]

My 05 makes a noise that sounds like air blowing over a bottle, maybe what others describe as a whirling noise. Only happens when the AC is on, and though not constant, happens a lot (like most of the time)-any ideas on this would be greatly appreciated.

Thanks!

 

[greg92jeepxj]

Check that all vents are working properly . If that is not the case , the evaporator may be icing up and causing wind turbulence inside the module where the evaporator and heater core live. Is the a/c compressor cycling when this happens ? If you only notice this on extremely hot days when the a/c compressor isn't cycling as often due to high humidity then it is likely the evaporator may be icing . I don't know if your system uses an a/c thermostat that senses evaporator temperature of if it cycles the compressor using readings from the high pressure switch but it can't hurt to make certain the high pressure switch is working right . The high pressure switch is an important component , without it , the head pressure can easily be exceeded and that's harmful to the life of the compressor. On my '92 , its a simple blow off valve on the drier but your system is an accumulator type so the high pressure switch will be on the compressor. You can pull the plug off and temporarily install a fused jumper just for test purposes into the plug . Then , check the switch with an ohm meter . I don't know the spec's on it but if you can find out , that will be helpful to know. If spec's not available , just test it with system off before the a/c has been running so pressure is low and record reading . Check it again while the system is running with the fused jumper installed and record that reading . The fact that the readings are different substantially should be good but spec's are always good to go by . Hope this helps . Be advised , the circuit may be computer feedback so be mindful not to use anything that will draw excessive amperage to jump out the high pressure switch harness plug.

 

[JPNinPA]

Being there is no filter in this system anything could be in a vent.
Could be a blend door issue. Not closing all the way causing a low pitched whistle.

 

[Chris10]

Thanks for the replies. I looked/listened a little closer and it only make the sound when something is cycling on and off, makes a clicking sound, then it will make the noise, then it will click again, and the noise goes away, this just cycles through. I live in Savannah, GA, so it hot and humid a good part of the year here.