Noise hours after turning off car

Zaxcom · 11-05-2009, 10:28 AM

I got home form work last night at 5pm, turned off the car and went inside. At midnight I went out to the garage to take out the garbage and there was a whirring motor sound coming from the rear of the car. The car was off, the keys were inside the house but this motor sound kept going. It was not coming from the engine area, most definitely from the rear of the car.

I looked at the dash and all the lights were out except for the one red light that blinks when the car is off.

I tried cycling the power button but that did not stop the sound. So then I went and got my keys, and power cycled the car once again. This time the noise stopped.

What was it?

David Beale · 11-05-2009, 10:31 AM

Fuel vapour recovery system. The valves often "moan" when passing fuel vapour.

I could say "RTFM", but that would be rude.

But do so anyway.

Bobsprius · 11-05-2009, 10:32 AM

It could be part of the Venting of the Gas Tank, Hybrid Fan motor, I hear them as well, in fact my S.O. told me the other day, that noises were heard 8-10 hours after I got home from work and as they were getting into their car in the Morning.

I first thought...No, your crazy or hearing things, but I know it happens, just can't tell you what they are specificially. Some of the more "Techno Posters" I hope will explaing them because Now at least I feel normal....someone else hears them too!

I do know they are "Normal"

Zaxcom · 11-05-2009, 10:33 AM

This was no moan, it was a running motor or fan and it went on for at least 5 minutes that I was out there, and was already running when I went into the garage. Medium to high pitched whirring sound.

qbee42 · 11-05-2009, 10:35 AM

I don't know if the Gen III has the same system, but on the Gen II you also have a fuel system pressure test which runs several hours after the car is shut down. It makes the noise you describe.

Tom

tumbleweed · 11-05-2009, 10:37 AM

Just in case, make sure your gas cap is on correctly. If it were leaking air into the tank the pump might run longer than usual trying to clear vapors out of the tank.

Zaxcom · 11-05-2009, 10:39 AM

Its kind of like the car is never really off. Its little computer brain is always up to something.

Zaxcom · 11-05-2009, 10:44 AM

nvm, duplicate post.

ken1784 · 11-05-2009, 02:16 PM

On page-22 of owner's manual, it says...

Noise from under vehicle after turning off the hybrid system
"Approximately five hours after the hybrid system is turned off, you may hear sound coming from under the vehicle for several minutes. This is the sound of a fuel evaporation leakage check and, it does not indicate a malfunction."

Ken@Japan

Zaxcom · 11-05-2009, 02:26 PM

thx i feel better now.

11-05-2009, 10:28 AM	#1
Zaxcom Senior Member Join Date: May 2009 Location: NC Posts: 102 My Car: 2010 Prius Model: III Package: No Package Thanks: 1 Thanked 11 Times in 10 Posts Friends: 0	Noise hours after turning off car I got home form work last night at 5pm, turned off the car and went inside. At midnight I went out to the garage to take out the garbage and there was a whirring motor sound coming from the rear of the car. The car was off, the keys were inside the house but this motor sound kept going. It was not coming from the engine area, most definitely from the rear of the car. I looked at the dash and all the lights were out except for the one red light that blinks when the car is off. I tried cycling the power button but that did not stop the sound. So then I went and got my keys, and power cycled the car once again. This time the noise stopped. What was it? __________________ 2010 Prius III Blue Ribbon Metallic 2008 SMART For Two Silver/Black 2002 Honda CR-V LX Silver 1997 Honda Civic LX Aqua Blue

11-05-2009, 10:31 AM	#2
David Beale Senior Member Join Date: Jul 2006 Location: Edmonton Alberta Posts: 2,118 My Car: 2007 Prius Model: Package: B Thanks: 3 Thanked 77 Times in 58 Posts Friends: 0	Re: Noise hours after turning off car Fuel vapour recovery system. The valves often "moan" when passing fuel vapour. I could say "RTFM", but that would be rude. But do so anyway.

11-05-2009, 10:32 AM	#3
Bobsprius BobPrius Join Date: Jul 2009 Location: Buffalo Posts: 441 My Car: 2010 Prius Model: V Package: Adv. Technology Thanks: 9 Thanked 39 Times in 36 Posts Friends: 1	Re: Noise hours after turning off car It could be part of the Venting of the Gas Tank, Hybrid Fan motor, I hear them as well, in fact my S.O. told me the other day, that noises were heard 8-10 hours after I got home from work and as they were getting into their car in the Morning. I first thought...No, your crazy or hearing things, but I know it happens, just can't tell you what they are specificially. Some of the more "Techno Posters" I hope will explaing them because Now at least I feel normal....someone else hears them too! I do know they are "Normal"

11-05-2009, 10:33 AM	#4
Zaxcom Senior Member Join Date: May 2009 Location: NC Posts: 102 My Car: 2010 Prius Model: III Package: No Package Thanks: 1 Thanked 11 Times in 10 Posts Friends: 0	Re: Noise hours after turning off car This was no moan, it was a running motor or fan and it went on for at least 5 minutes that I was out there, and was already running when I went into the garage. Medium to high pitched whirring sound.

11-05-2009, 10:35 AM	#5
qbee42 Senior Member Join Date: Mar 2006 Location: Northern Michigan Posts: 10,504 My Car: 2006 Prius Model: Package: #7 Thanks: 95 Thanked 392 Times in 290 Posts Friends: 10	Re: Noise hours after turning off car I don't know if the Gen III has the same system, but on the Gen II you also have a fuel system pressure test which runs several hours after the car is shut down. It makes the noise you describe. Tom

11-05-2009, 10:37 AM	#6
tumbleweed Senior Member Join Date: Oct 2005 Location: Eastern Oregon Posts: 1,692 My Car: 2010 Prius Model: V Package: Adv. Technology Thanks: 33 Thanked 105 Times in 84 Posts Friends: 0	Re: Noise hours after turning off car Just in case, make sure your gas cap is on correctly. If it were leaking air into the tank the pump might run longer than usual trying to clear vapors out of the tank.

11-05-2009, 10:39 AM	#7
Zaxcom Senior Member Join Date: May 2009 Location: NC Posts: 102 My Car: 2010 Prius Model: III Package: No Package Thanks: 1 Thanked 11 Times in 10 Posts Friends: 0	Re: Noise hours after turning off car Its kind of like the car is never really off. Its little computer brain is always up to something.

11-05-2009, 10:44 AM	#8
Zaxcom Senior Member Join Date: May 2009 Location: NC Posts: 102 My Car: 2010 Prius Model: III Package: No Package Thanks: 1 Thanked 11 Times in 10 Posts Friends: 0	Re: Noise hours after turning off car nvm, duplicate post.

11-05-2009, 02:16 PM	#9
ken1784 SuperMID designer Join Date: Dec 2003 Location: Yokohama, JAPAN Posts: 2,000 My Car: 2010 Prius Model: N/A Package: G Thanks: 11 Thanked 278 Times in 129 Posts Friends: 8	Re: Noise hours after turning off car On page-22 of owner's manual, it says... Noise from under vehicle after turning off the hybrid system "Approximately five hours after the hybrid system is turned off, you may hear sound coming from under the vehicle for several minutes. This is the sound of a fuel evaporation leakage check and, it does not indicate a malfunction." Ken@Japan

11-05-2009, 02:26 PM	#10
Zaxcom Senior Member Join Date: May 2009 Location: NC Posts: 102 My Car: 2010 Prius Model: III Package: No Package Thanks: 1 Thanked 11 Times in 10 Posts Friends: 0	Re: Noise hours after turning off car thx i feel better now.

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Have my Prius for 3 hours!	Bookwyrm	Newbie Forum	2	05-29-2009 10:18 PM
Pelosi's first 100 hours	dragonfly	Fred's House of Pancakes	3	11-11-2006 10:00 PM
T minus 5 hours...	yarzy	Gen II Prius Main Forum	4	09-08-2006 10:25 AM
Want to get $100 for 2 hours of your time?	inPlacentia	Gen II Prius Main Forum	0	02-09-2006 08:00 PM