Strange Sound When Turning-Off VUE...

[jmatero]

Last night, after turning off my VUE 5-speed, I heard and "winding down" noise... like a plane landing kind of sound that lasted about 5 seconds after the engine is stopped. I restarted and opened the hood and saw the cooling fan was on so I assumed it was the sound of the Fan winding down... however, I drove the car into Saturn Service less than a mile away this morning and in the lot, it happened again when shutting down. I doubt the car was hot enough after that brief ride for the cooling fan to be on. I heard the SAME EXACT sound on my old Mercury Sable when shutting down and was "told" it was my torque converter.... but that obviously isn't the case here. As some of you know, I've had a HARD time getting my new VUE into 1st gear... do you think this is related? The car only has 300 miles and I'm so worried it is something major with the tranny or something... I really don't want a one-week old car to have an engine/tranny pulled apart or something. Anyone heard of this issue? Any suggestions?

[crawfordna]

Did you have your defrost on? My car makes the same noise when I shut it off and have either A/C or Defrost on. The compressor is winding down.

--Nick

[03Vue]

If its reproducible, pop the hood and have someone stand by it as you shut it off. (to see where the sound is coming from)

Was the whirring sound mechanical like something in the tranny spinning, or was it more like a fan blade?

What's the problem getting it into first gear? If its when your going 15mph+ (like coming up on a stop sign) it could be the syncros in the tranny. If so, wait till your slowed down or don't push so hard on the shifter.

-Joe

[jmatero]

Problem solved guys.... there was a "STALL" error code that when cleared turned the cooling fan off.... it was running continuously.

[Tatusmi]

Originally posted by crawfordna
Did you have your defrost on? My car makes the same noise when I shut it off and have either A/C or Defrost on. The compressor is winding down.

--Nick

yea I get the same thing.

- Tatusmi

[jmatero]

It's not the compressor.... the compressor stops turning when the engine does. The noise you hear is the cooling fan winding down. When the AC Compressor is on, the cooling fan comes on as well.

[OhioVueBoy]

Originally posted by jmatero
It's not the compressor.... the compressor stops turning when the engine does. The noise you hear is the cooling fan winding down. When the AC Compressor is on, the cooling fan comes on as well.

No, if the compressor is engaged when you turn the engine off, it will spin down, which wish as well balanced as these are when new, can take 20-30 seconds... I see it all the time on S cars at work if you shut them off with the A/C on, since the compressor is so open.
~D.J.~

[bigbird]

Most A/C compressore these days use swash plates to operate their pistons They don't even have a crankshaft with connecting rods that could maintain some inertia. Maybe the pressurized R134A keeps the pistons moving, causing the swash plate to wobble, giving the impression that the compressor is still turning. After the system loses pressure, the swash plate would stop wobbling. Sound plausible?

[jmatero]

I can only speak for me.... but the sound I'M talking about sounds like a plane landing... whining that lasts 5-10 seconds after shutdown. It was, indeed, the cooling fan. I've worked on cars all my life and have NEVER heard of an AC compressor "spinning" down after the car stops.... in fact, a number of car makers actually engage the AC as the engine is turned off to prevent run-on as the drag will stop a 4-cyl. dead in it's tracks. But an AC compressor turning 20 seconds after a motor stops? If it spins that easily, it wouldn't drag down an engine while driving. HOWEVER...... when the engine stops with the AC running, you WILL hear the sound of pressurized gas in the system hissing away for 15-30 seconds. That's normal, and it can be loud, but it's not the compressor spinning down.