Loud Fan Noise
06-29-2001, 05:36 AM
#3
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I've noticed the same thing now that hot weather has arrived in the Midwest...
It's in the engine compartment, and I think it's a combination of the radiator fan etc. and the A/C compressor. The combined noises are fairly spectacular for a car. When turning the car off, it sounds like a jet engine spooling down.
After you turn the car off, you'll also notice a gentle hum from a water pump which continues to run for several minutes.
I don't think any of this is indicative of a problem.
After you turn the car off, you'll also notice a gentle hum from a water pump which continues to run for several minutes.
I don't think any of this is indicative of a problem.
06-29-2001, 05:53 AM
#4
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Yup, all regular stuff especially on the 2.7T
The "Jet engine" noise has been mentioned here before. If I remember rightly, it's a fan attached to the engine crank that is clutched under electronic control so you only hear it when the engine's hot enough to need it. When you pull away from a standing start you will hear a "Whooosh" sound that picks up speed with engine speed and is loud enough to hear in the cabin with the windows up (makes pedestrians look too!).
As for other noises, the "spooling down" noise that BobTA6 mentions is the water pump for the turbos on the 2.7T which will run coolant through for a few moments to prevent oil from coking in the turbos if they are hot when you shut down. This should prevent the need to idle for 5 minutes before shutting down with hot turbos, but I'd always suggest taking the last couple of minutes of your drive at a slightly steadier pace if you can just to bring temps down a bit first.
You may also sometimes hear a hissing/bubbling sound after shutdown - this is just coolant from the A/C compressor (it's under pressure when the compressor runs and of course when you switch off you lose the pumping pressure and it probably just bleeds back or something).
As for other noises, the "spooling down" noise that BobTA6 mentions is the water pump for the turbos on the 2.7T which will run coolant through for a few moments to prevent oil from coking in the turbos if they are hot when you shut down. This should prevent the need to idle for 5 minutes before shutting down with hot turbos, but I'd always suggest taking the last couple of minutes of your drive at a slightly steadier pace if you can just to bring temps down a bit first.
You may also sometimes hear a hissing/bubbling sound after shutdown - this is just coolant from the A/C compressor (it's under pressure when the compressor runs and of course when you switch off you lose the pumping pressure and it probably just bleeds back or something).
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06-29-2001, 07:11 AM
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Me too.
Auxiliary radiator fan for when the engine gets really hot. Sounds just like an air raid siren. Goes on an off (If it gets cool enough.) If it stays on, it might mean your relay is shot. Wife said disapprovingly, "A car like this shouldn't make a sound like that." I think it's kind of cool. Reminds me a little of the Batmobile circa 1965.
