AC blows warm air when outside temp is over 100F

[BoogieBot]

Just as the title says. First noticed this last summer when driving through the Mojave desert at night - the NWS said the outside temp was about 107F, and my A/C blew slightly warm air on both settings (max was a little cooler). Recently drove to Phoenix, where it was 96F out. Noticed my A/C blowing cool, not cold, air. However, in another location, the outside temp was 85F and the A/C blew cold air.

When I turn on the a/c, I hear a rapid "thuggathuggathuggathugga" noise from somewhere behind the dash. It starts loud and gets quieter quickly. Not sure if it ever stops, or if the 2.5L motor just drowns the sound out.

Is my compressor on the way out? A/C clutch not engaging? Low of refrigerant? Something else?

Thanks in advance.

 

[jeremysdad]

You might check your charge, but ac can only lower air temperature so much*, and the less humidity in the air the more you'll notice it. Can't remember the general range, but really shows when the temperature is over 90. Max ac and Windows up is your friend, as you essentially seal the environment and create a refrigerator environment. Lol. (Max ac was originally 'recirculate' on car ac)

*without freezing up

 

[adsm08]

Without actual temp readings it is hard to say if it is working properly, but a number of things can affect AC performance, and outside temps above 100* can put a big hurt on the AC.

Generally speaking, in MAX, you should be able to get the register temp down to no more than 40* regardless of outdoor temps.

A thunking in the dash usually means a blend or mode door actuator is getting weak and needs replaced. This may be part of your issue.