Horrible A/C noise at idle

[Jackhill442]

My '96 XJ with 180K makes a horrible moaning sound occasionally at idle. It is not the fan belt. If I rev the engine during the noise, it goes away, but returns when the engine comes back to idle. The air blows very cold, though. The noise is just very annoying. It is like a vibration in the line, when I bend it, it stops for a while, but always returns. Any answers? I don't want to spend very much on the A/C because I don't use it that much, but this noise drives me crazy. Help appreciated.

 

[pabloconrad]

I don't want to spend very much on the A/C because I don't use it that much, but this noise drives me crazy. Help appreciated.

Being as you live in the "Hot-lanta" area, I'd expect you to use it often.

As for the noise, sounds like you have a bearing going out. Groaning is often a sympton of bearing wearing out.

 

[Jackhill442]

A bearing in the compressor or the blower fan?

 

[bchulett]

My '96 XJ with 180K makes a horrible moaning sound occasionally at idle. It is not the fan belt. If I rev the engine during the noise, it goes away, but returns when the engine comes back to idle. The air blows very cold, though. The noise is just very annoying. It is like a vibration in the line, when I bend it, it stops for a while, but always returns. Any answers? I don't want to spend very much on the A/C because I don't use it that much, but this noise drives me crazy. Help appreciated.

I just had my XJ in the shop for the same thing ... new OEM compressor is $510. It's a matter of time until that bearing will finally seize. I got 160K miles out of mine ... I can't complain.

I use it daily ... even in the winter. If I'm not mistaken, it cycles on when the defroster is in use ... may want to check that out before discarding the compressor.

Good luck.

 

[BIGSLVRXJ]

mine does the same thing after i dumped r 134 in on top of the r 12. I was real smart on that one. The compressor has 200k on it though and it was rigged so thats not bad i guess.

 

[Jackhill442]

Yeah, I could understand if it is the compressor, but it has been doing it for 80,000 miles and it hasn't gotten any worse, and it blows ice cold air. I don't get it.

 

[bchulett]

Yeah, I could understand if it is the compressor, but it has been doing it for 80,000 miles and it hasn't gotten any worse, and it blows ice cold air. I don't get it.

How long have you owned your XJ ? Did you mean 180K or 80K miles ? Or it's been doing this for 80K miles ?

Since mine was new, the compressor made a "moaning" or "howling" type sound ... it's a 1991. The dealer told me it's inherent to the XJ---so I've lived with it over the past 13 years.

But, over the past couple years, that sound has changed some .... incorporating what appears to be a rattle with some vibration ... again noticable mostly at idle. On occassion, I will get a low-speed groan out of the compressor ... kinda sounds like the brakes on a 16-wheeler coming to a stop. The other noticable symptom, is what appears to be more drag on the engine when the AC is engaged.

I noticed if I crank the engine in the morning a few times (without actually starting it), after the starter and engine stops turning, for a short moment, I can hear a pully continue to turn while making a scraping type sound. I know it's the compressor because everything on the serpentine is new, except for the harmonic balancer and AC compressor---and it's only one of two components on the belt with a clutch-driven device. The other component is the viscous fan ... and that was recently replaced.

At 180K miles, bearings on the serpintine will eventually go bad and they need to be replaced. At 80K miles ... well, that seems to be premature.

Good luck.

 

[Jackhill442]

bchulett, I was told the same thing about the noise, that it is normal and just to live with it. It does sound just like a 16 wheelers brakes, and it is horrible and embarrassing. If it is normal, why does no other make of car on the planet do it? The Jeep has 180,000 miles, and the noise has been there since around 100,000 miles. Should I look into compressor replacement, or is there no way to have a silent A/C system? Thanks for your message, any further help is greatly appreciated.

 

[pabloconrad]

I don't want to spend very much on the A/C because I don't use it that much, but this noise drives me crazy. Help appreciated.

You could have the freon removed (Federal law, EPA), the unit removed and then install an air compressor.

 

[bchulett]

bchulett, I was told the same thing about the noise, that it is normal and just to live with it. It does sound just like a 16 wheelers brakes, and it is horrible and embarrassing. If it is normal, why does no other make of car on the planet do it? The Jeep has 180,000 miles, and the noise has been there since around 100,000 miles. Should I look into compressor replacement, or is there no way to have a silent A/C system? Thanks for your message, any further help is greatly appreciated.

Well, all I can say is there is a noisy "howl" or "whine" that comes out of these compressors when new, it seems to be more noticeable approximately 1 year after purchase. And, I've been told for the past thirteen years it's "normal"... but I believe what you and I are hearing isn't normal.

I'm not a hypochondriac ... I don't enjoy throwing money away... but I know when a bearing is singing and ready to seize. I've been around large printing equipment for the past 30 years ... rollers, dies, pumps, bearings, motors and compressors galore---even with all that noise, I can hear a bad bearing.

So, I've had mine at the dealer for the past few days to diagnose this problem ... I told them it's random, happens mostly when hot, sometimes when cold, but only slightly above idle. They couldn't repeat the problem until the second day ... then finally said: "your compressor bearing is going bad"---no sh*t!

As a result, a new factory compressor is on order ... will be installed sometime next week.

I will advise with results.

Bob

 

[cito57]

Mine does the same thing and I've got 160K. Had a mechanic tell me to replace the blower motor and resistor. I did that, and she's still-a-howlin'. I'll try the compressor next. A suspension rebuild is in order first. Oh yeah, then a new radiator. Is there a light at the end of the tunnel?

 

[BIGSLVRXJ]

If a bearing freezes in the compressor will it throw the belt off and snap it?

 

[Yucca-Man]

If a bearing freezes in the compressor will it throw the belt off and snap it?

That's pretty likely if any pulley stops freely rotating. You'll probably burn straight through the belt in such an event. Water pump will stop spinning and engine temps will jump drastically...

 

[Jackhill442]

Thanks bChulett, definitely let me know if it fixes the problem and what the cost is. I definitely don't think it is a blower fan. I just wonder why the problem has not gotten any worse over the last 80,000 miles. You would think the damn compressor would have seized up by now or just quit engaging. Thanks for the help,
Jack

 

[bchulett]

Thanks bchulett, definitely let me know if it fixes the problem and what the cost is. I definitely don't think it is a blower fan. I just wonder why the problem has not gotten any worse over the last 80,000 miles. You would think the damn compressor would have seized up by now or just quit engaging. Thanks for the help,
Jack

Hello Jack,

Well ... I've got good news and bad news.

Good News:
The new compressor made a significant difference in the noise department ... no rattling, grinding or howling like an 18-wheeler. Plus the excessive drag on the engine when the AC is engaged, is essentially gone. Perfect .. fixed that problem.

Parts Cost
OEM Compressor (PN 56004354) .... $504.00
Dyes Leak R12 (PN 5010044-AA) ... $6.70
Refrigerant R12 (PN 82300328) ...... $79.00

Labor Cost .... $220.00

Total w/tax ... $855.40


Bad News:

1. The Tustin Dodge Dealer work order indicates "it may have a leak"... "dropped 1/2" in 30 mins" (whatever that means).

2. The work order also indicates "may be R12 machine" (why they didn't take the time to rule out their R12 machine is F...'n beyond me).

3. My AC now only cools down to a mear 48˚ - 52˚ degrees in 80˚ weather. It was way better than that before they changed out the compressor ... I don't even see any condensation dripping on the ground ... not like it was. What's up with that ?? ... I thought all AC units dripped condensation.

4. Here I go again having to spend more time and money on "high cost ... poor quality service". Let's just release it to the customer and wait until they complain type attitude----this is the very reason why I won't buy another Chrysler product. They can shove those "Five-Stars" straight up their ass.

Good luck with yours ...
Bob

 

[AZ Jeff]

As Eagle and some others can attest from my time on this forum, I am pretty meticulous about maintaining a vehicle, so take what I say in that vein:

My old '92 had the NOISIEST compressor I ever heard on a car, even worse than my dad's 1968 Ford with the old 2 cylinder York compressor. However, that old XJ DID make cold air, with R12 (and I live in Phoenix, so it got used a LOT!). I checked the pressures with a manifold, and the clutch current draw with an ammeter, so I knew that all was well.

I just learned that, at idle in traffic, I would be happy listening to the compressor come on and off, growling away, knowing full well that all was just fine, even if it was noisy.

It did that for 80K miles, until some kid smacked it from behind at 45mph, and totalled it.

My advice--just listen to it, and if it changes tone, level, etc., then go digging into it further. Otherwise, if it's cold, don't get TOO concerned. (Especially for the price of a compressor!!)