[cactusleaf]

I just took my 900S in for a new exhaust pipe and muffler, which cost me lots of money. Since I retrieved it from the shop, a strange thing has been happening. (I don't see how it could be related to exhaust work.)

While driving, with A/C on, every so often I'll hear a split-second squeal sound coming from in front of me.. somewhere behind the dash? maybe from the wheel well? It's hard to tell. Accompanying the sound is a small, almost unnoticable lurch of deceleration. The squeal lasts from 1/4 second to maybe 1/2 second. I'm thinking it's a belt slipping, mayyybe on the compressor. Does this sound right?

Also my CV joint problem (pop pop pop while hard turning) on the left front wheel got noticably worse since the new exhaust was installed.. I'm just hoping the squeal and lurch doesn't have anything to do with a wheel that's about to fall off. Anyone ever hear of this squeal thing before?

I appreciate all the help you guys have given me so far!

 

[ejenner]

could be the A/C clutch

 

[Jezzadee]

My squeal and lurch was caused by worn driveshafts. They would slip a little pulling away, causing a metallic squealing and a brief lurch. No a/c on mine.

 

[ejenner]

noise is from behind the dash and only happens when the A/C is on

 

[Jezzadee]

Oh yes, a likely story Anyway, I can hardly be expected to notice every little detail in these threads :lol: .




;oops:

 

[ejenner]

ah well. spose not. :roll:

 

[woywitka]

don't think the exhaust work would have anything to do with these issues. i too get a really loud scream from the car when i turn the a/c on and accelerate the first few times. no ideas!

 

[DrSquirley]

Certainly sounds like it could be the ac compressor. What part of upstate are you from?

-Alex

 

[cactusleaf]

Dear Dr. Alex Squirley: I'm right outside of Syracuse. Potsdam is farther north than I've ever been in this state. Must be cold up there (har har).

I do think it has something to do with the AC. I don't hear it every time I drive or every time I turn the AC on, but it's never happened with AC off. If it's a slipping compressor belt or something, would I just need to change the belt?

Oh and what is the compressor clutch? I have never heard of such things (or many things really).

Haha, Jezzadee you are forgiven.

 

[Matthew]

My squeal and lurch was caused by worn driveshafts.

So which bit exactly was worn? Having just dismantled the front-end of a 900, I am currently interested in all things driveshafts shaped ;oops:

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[cdaly]

While driving, with A/C on, every so often I'll hear a split-second squeal sound coming from in front of me.. somewhere behind the dash? maybe from the wheel well? It's hard to tell. Accompanying the sound is a small, almost unnoticable lurch of deceleration. The squeal lasts from 1/4 second to maybe 1/2 second. I'm thinking it's a belt slipping, mayyybe on the compressor. Does this sound right?

Sounds like the sort of symptom you might get from a compressor starting to seize. You said it never happens when the A/C is off? So it only happens while the compressor internals are in motion. Is the A/C cooling? It could be the compressor clutch slipping against the pulley due to an internal seizure or it could be the belt slipping on the pulley. Either way, an internal seizure is the only thing that would cause engine drag...

 

[DrSquirley]

Dear Dr. Alex Squirley: I'm right outside of Syracuse. Potsdam is farther north than I've ever been in this state. Must be cold up there (har har).

I do think it has something to do with the AC. I don't hear it every time I drive or every time I turn the AC on, but it's never happened with AC off. If it's a slipping compressor belt or something, would I just need to change the belt?

Oh and what is the compressor clutch? I have never heard of such things (or many things really).

Haha, Jezzadee you are forgiven.

"It could be the compressor clutch slipping against the pulley due to an internal seizure or it could be the belt slipping on the pulley. Either way, an internal seizure is the only thing that would cause engine drag..." -cdaly

Thats what it sounds like to me. By the by one of the guys i live with is from the 'cuse. And it does get cold. I heard you got some flooding though the other day.

-Alex

 

[Jezzadee]

So which bit exactly was worn? Having just dismantled the front-end of a 900, I am currently interested in all things driveshafts shaped ;oops:

Not exactly sure as I never saw the old ones. I know there was too much play in them, they were dry with no grease inside, and I was told they were "badly worn". Car drives much better now. When it starts, that is .

 

[cactusleaf]

Ah thank you Cdaly and Alex, that sounds right on. Engine drag is exactly what it is. That's basically what I was picturing in my head, the belt dragging against the compressor pulley and taxing the engine. Although that mental image was just blind intuition.. but it's a miracle to hear it corroborated by someone who knows.

Now I'm not so worried because the AC is just barely working anyway, and I prefer my sunroof open

Yeah Alex, man it rained bathtubs here and basements flooded (incuding ours) all over the place. I got to drive the Saab through rain for the first time! No leaks, AND it feels like it's just glued to the road!!

 

[cactusleaf]

Uh Oh

Update: the squeal has changed and gotten worse.. and happens with A/C on OR OFF! Also the tiny lurch is barely noticable and doesn't seem like any significant engine drag. The longest squeal was last night, about 7 seconds long.. and it finally faded and went away when I slightly let off the gas. I was driving straight at about 60-65 mph.. I never hear a squeal at lower speeds. It's really disconcerting.

Oh hey Jazzadee, this squeal sounds exactly like old cars pulling away from a stop, like the tie rod problem you had.. except it happens randomly at speed. It makes me shiver.

 

[ejenner]

It could be this then http://www.saabcentral.com/forums/showthread.php?p=479106#post479106

Would be better if it were the A/C clutch though.