Subaru WRX Forum banner

AC Compressor Whine

2K views 16 replies 5 participants last post by  pumm3l 
#1 ·
This noise just started recently when the cold weather started. I have a stethoscope and I'm pretty sure I narrowed it down to the AC compressor, it's the only place that I can really hear the noise.

What would cause the AC compressor to whine? It still blows cold air, seems like it has a full charge because it's not really surging when I have it on.
 
#2 ·
Can you describe the whine a little better? Is it tied to engine speed?
 
#5 ·
have you checked the idler pulley? one of our cars did that and it happened to be the idler pulley and a lose belt tensor
 
#8 ·
I'd like to know the answer to this as well (i.e., which specific parts to replace), as I'm having the exact same problem. I also used a mechanic's stethoscope and found the noise was loudest when I placed the tip on the adjuster bracket (part # 73623A in that photo) just in front of this pulley.
 
#10 ·
I bought the idler pulley a few weeks back. I haven't had a chance to put it on though, it's just been so damn cold and mixed with a little bit of laziness makes a bad combination.

As soon as I put it on I'll let you know if the noise goes away.
 
#12 ·
eh, so this thread got me off my ass and I finally put on the pulley today, noise is 100% gone. Took me about 15 mins to take it off and put on the new one.

Part no. from Subaru is 73131FC000 -- I paid $25 for it. Glad that's all it was a few people mentioned AC clutch which was what I was planning on doing until I came here.
 
#13 ·
Awesome, glad it worked for you!! Thanks for posting the results. I'm almost 100% positive that this is what is wrong with mine. IIRC, the bad clutch causes noise basically whenever the compressor switches on, whereas this noise occurs all the time, and is RPM dependent (and not related to the transmission). I'll post up as well after I replace mine.

Is there any reason to replace the other piece that you were asking about?
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top