Strange noise after running AC for more than 20 minutes...

I have an MCS and after running the car for more than 15-20 minutes with the AC on (today we -=PHX=- had our first 100F day of the year), I heard a strange whining noise. Much like that of a MOSFET transistor trying to modulate. This happens at certain load requirements of the engine. All three times it happened on the freeway (65-75 MPH) and it only did it with acceleration. It would start it's wierd whining noise then after about a half minute disappear until I stepped on the throttle again in just the right way. The sound is emminating from the center of the dash area.

I noticed this a couple of times before and thought it might have to do with the car being new. I now have 5200 miles on it and now it is starting to concern me. It only does this with the AC on. Hmmm.

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Happy Motoring!

 

I've had something similar, that I've only noticed since my first oil change last week. Sounds like the A/C is trying to imitate the supercharger, only much louder, while accelerating or decelererating with high engine RPMs on a very hot day. Shifting to a higher gear (lower RPMs) makes it go away, as does turning off the A/C.

Strange.

Oh well, I have the windows and sunroof open 99.9% of the time its not raining, unless it is a prolonged highway drive. So I rarely use the A/C.

~Joe

 

That's a well known and unresolved flaw. Happens whenver recirculate is selected at speeds above 70Mph.

 

>>That's a well known and unresolved flaw. Happens whenver recirculate is selected at speeds above 70Mph.

Thanks!! :smile:

 

Thats funny, cause if we're talking about the same thing, I've heard it in first and second gear, as well as at higher speeds!

Oh well, no big deal!

~Joe

 

I have a deffint whistle in mine,, that has nothign to do withthe speed of teh car,, becasue it goes awys when I turn the fan up and down.... do you have auto ac or regular ac? ,ine auto AC

 

Mine whines too, intermittently, at low speeds. Sounds almost like a whistle.

 

I hear mine once and a while at low speed, (usually can't hear much else at high speed other than wind.. ), but it sounds like normal AC noise to me...

Rocketboy_X