A/C Buzzing

[KurtAZ]

Hey all;

I have been trying to figure out what is going on with my AC in my 1995 Passport. It works fine if you are going but as soon as you drop into idle it starts buzzing like an angry bee (sorry, that is the only way I can think of describing it). Any ideas? I am thinking belt or tensioner....

[CN2005]

Does your A/C still cool well? If not, then you may have a leak in the system and that buzzing noise is the compressor reed valve starving for lubricant. Best bet is to have a trusted A/C shop evacuate the system, check out the condition of the A/C oil and refill if there are no problems.

Best of Luck!

[KurtAZ]

Yeah, it still cools...at speed but not during stop and go driving. I'll try what you suggested. Thanks.

[avraajan]

exactly i have the same problem as yours, please let me know what you found out

Originally Posted by KurtAZ

Yeah, it still cools...at speed but not during stop and go driving. I'll try what you suggested. Thanks.

[CN2005]

This may sound a bit odd but I am curious if your crankshaft flywheel is slipping at low RPMs causing your A/C compressor to buzz. I had the same problem happen recently (after several compressor changes and it wasn't even the compressor!!)

Try this:
With the engine off, get a marker pen and mark a line on the top of the crankshaft pulley, across the belts, from the engine towards the front. Next. Start your engine with A/C on so you can hear the buzzing. Stop the engine, check the position of the marks, if they are off then its safe to say your harmonic dampener (rubber sleeve between the top and bottom pulley assembly) is shot. Note: you cannot see the harmonic dampener until the crankshaft pulley is removed from the engine.

If its your crankshaft pulley that is faulty you will save a ton of $$$ and frustration avoiding a complicated A/C compressor replacement.

best of luck!

[Mach7]

Did you ever get this resolved?

[AuburnRyan]

My 95 buzzes and vibrates on position "4" only...I can feel it in the seats as well!?

Going to change the belts this week because they are bad - hopefully the ac belt replacement will fix?

[KurtAZ]

Originally Posted by Mach7

Did you ever get this resolved?

Nope, evacuated and filled back up with Oil/134a mixture (small can) and topped off with regular 134a. Still working on it though. I may look at the belts this weekend. It only happens at idle so it could definately be a belt slipping.

[Mach7]

I replaced my compressor and it got rid of the buzzing and fixed the cooling issue at idle...

[tomlcollins]

This has just started happening to me, but only at idle. The a/c is still working at idle.
The buzz is very annoying, and I'm REALLY hoping it doesn't mean the end of my compressor. I will sell my Rodeo before I shell out $1500 to fix the a/c.
I guess I will try replacing the serpentine belt first, although I don't think it will make a difference. Any other ideas?

[AuburnRyan]

Mine has something to do with my core inside the cabin, it can be lessened by placing my foot behind the glovebox...

[Mach7]

Originally Posted by AuburnRyan

Mine has something to do with my core inside the cabin, it can be lessened by placing my foot behind the glovebox...

Check to see if a piece of paper or something has fallen down behind the glove box. Open the glove box, remove contents, press in hard on the left side to allow it to fold all the way open. The fan is actually open and not covered. I had something fall out of the glove box and make contact with the fan... Maybe that's your problem...

It cost me under $800 to replace the dryer and compressor (fresh rebuilt) which included labor. I had wasted my money with a take off compressor first... Live and learn as they say, that was money thrown out the window.

Good Luck!

[2eyefishclaw]

the newer compressors just dont hold up as well as ther older ones I have replaced mny of them with reed valve problems