Louder than normal noise under hood when running AC

It is possible that there is something wrong in the compressor. Have you had any service done on the AC? If so, was it done by Toyota? If not, the wrong type of refrigerant/oil might have been used. I was quoted $150 by Toyota to evacuate the AC system, refill with Toyota approved refrigerant, and check system for leaks.

 

Or the AC condenser fan? That's the big radiator up front.

I think the posts above are right, it's the compressor, but the fan's another source of noise to consider, whenever AC's running.

 

if you can't get it to make the sound for the dealer, than obviously something is intermittently wrong.

it's a variable speed compressor. i'm not sure if the sound changes, but make sure you run it manually for the dealer, i.e., auto: off, fan: on, a/c: on.

 

yep, the sound changes with the compressor speed/
I checked it with the mini-vci & at the lower speed one can hardly hear it/
brought up to the max of 7500 it's noticeably humming/

dependent on outside & inside temperature the compressor starts with different speeds/
(meaning that sometimes you might hear it, sometimes you don't)

 

Well, if is a certified car, has your 12 month warranty run out?

 

Well, if is a certified car, has your 12 month warranty run out?

 

I had a similar issue with my 2010. The A/C sounded like your youtube video (louder than normal). When I took it to the dealer (who has always provided excellent service) they listened to it and said it was completely normal. What a relief! I understand a new compressor is very expensive.

 

regarding your video: sounds totally normal/
if you bring it to the dealer or know someone with a mini vci, the maximum output of the compressor can be throttled to reduce noise & vibrations/

 

how would you know which noise level is normal?
it could be that the louder one is normal & the more quiet one is just an early sign that the compressor might be failing soon/

 

It could be a hotter day when you are checking the new car. Hotter day means higher compressor speed. Do have a quick look at the fan behind the rad. There could be debris in there. Make sure it's off before you stick your hand in there (both car and fan)!!

 

Right. A lower thermostat setting would have a similar effect at the same ambient temperature.

 

If you have a ScanGaugeII you can program in the XGAUGE for air conditioner watts, and then just compare the reading to the sound. The car will run the compressor at different power levels depending on how much cooling the A/C controller wants. Mine seems to run anywhere from 1600 watts (seconds after starting after parking in hot sun), down to about 250 watts (cruising in mild weather just keeping the air comfortable).

At 250 watts it is pretty hard to hear, even standing outside near the hood and listening for it. At 1600 watts it sounds like a very small motorboat revving up to tow a miniature waterskier.

-Chap

 

I've just listened to your recording and the most prominent sound in it is your A/C compressor, it sounds just like mine when running near the max (1600 watt) output. You'd be getting max output if it was very hot in the car (say, just started after being parked in the sun) or you had the temp set way low, or both.

You should be able to hear the sound even more clearly by waiting for the engine to shut off so the A/C is all you hear. You should find that you can ramp the sound all the way up and all the way down just by playing with your temp setting. Set it lower, A/C ramps up. Set temp higher, A/C ramps down.

That way, you'll convince yourself that you know what it is, and you can relax and enjoy your car.

-Chap

 

this^