Gary95

Last year, my A/C stopped blowing cold air. So I took the car in to a Nissan dealer and they checked it out. I had the choice of either having the coolant/freon replenished, or completely replacing the compressor. After 10 years of service, I'd never had the A/C worked on. I assumed that it simply needed to be replenished (of course, that's the much cheaper route!). Well, it worked--the unit started blowing crisp cold air after being refreshed. I saved myself $460 from having to replace the whole thing.

However, just recently the compressor started making a rattling noise while it is engaged. No loss of cold air, just extra noise. It only happens when the auto climate control unit decides cold air is needed and activates the compressor. It's hard to notice the noise when driving at highway speeds or with the radio on moderately. But it's very noticeable when you have the hood lifted.

Any ideas on this? Is it possible something simple can be replaced? Or is this a sign that the compressor has finally had it? Can I "ride it out" until complete failure? If I can get another year of use before it goes, I'd rather do that. The complete replacement is very costly. I'm just concerned that the A/C compressor could fail at some point and cause other damage... unless Nissan has kept true to its fine engineering and A/C failure won't damage the engine.

Thanks in advance...

crazy97

iTrader: (1)

It could go out at any time. Mine made noise sometimes when it was engaged and sometimes when it was disengaged for about 2 months. When it goes out the pully on the compressor will stop turning and fry up your belt which also runs the alternator, you will see a lot of white smoke from under the hood when this happens and also you may have to change your pants, if you S*** them.
When mine went out it made a burning rubber smell about every 20 min before she blew. You can drive for a while without the alt. if your battery is good. If it gets noticably louder than it is now you may be at the end of it's life. There is a way that you can run the car with a different belt with out the AC, I don't know which belt to get or any part numbers, but guys have done it.

P.S. Don't plan any long road trips.

darrick

yeap me 2 running the short belt now

ultralighter

You can try to add a can of oil charge. The rattling noise is more than likely the reed valves. Adding oil to the systems has a 50/50 fix rate, and at worst it won't hurt the system. I assume you are running R134a. I would suggest a 3oz PAG 46 oil charge with dye.

Gary95

Hi Ultralighter -- thanks for the tip! However, I'm completely clueless about the A/C compressor. Is it fairly easy to add oil to the compressor? If you could provide some quick tips on doing so, I'd appreciate it. I'm assuming I can find PAG 46 oil at most auto parts stores, correct?

Hopefully this is all the compressor needs for the short run. I'd really like to delay getting a replacement for another year.

But Crazy97, you have a very good point -- I'll keep a short belt handy just in case the compressor goes. Thanks!

VeN0m

Why not replace the Idler pulley while your at it? The bearings in mine were locking up and it was making a wierd high pitched sound from time to time.

Yohann

This will blow your mind......but make sure the FANS are working!!!!!! A couple months ago my compressor started to make a noise similar to a loose timing chain and upon inspection of the A/C, it was the all due to the fans. I have no idea when, but both fans were dead. The engine never overheated because I run synthetic oil. It turns out that at low speed when the fans are off, you build up head pressure in the evaporator and the compessor starts that "knocking" sound because it can't pump against the pressure. When you get over 50 mph the fans usually shut off becuase there is enough airflow to cool the evap, so that's why you might not hear it at freeway speeds. The dealer**** wanted $340 for the fan pack, Autozone wanted $199, I found one online for $129 but did not want to wait for shipping......I got one at a salvage yard for $100, problem solved in 15 minutes.