Noise on start up

dmb40 · 10-09-2007, 06:16 AM

My 2007 has always booted up with an electric motor running in the left front of the engine compartment before the ICE starts. Recently it sounds quite different, almost like it is cavitating. All the fluid resoviors are full. Can you tell me what that pump/motor noise is and how to check it out?
Thanks,
Dave

qbee42 · 10-09-2007, 08:55 AM

Has it been cooler outside? The coolant transfer pump often makes a bit more noise when it is cold. The pump you are hearing transfers engine coolant to and from a thermos bottle so as to save the heat in the liquid as long as possible.

Tom

**efusco** · 10-09-2007, 09:27 AM

This is probably the 4th 'report' of this so far this season...perhaps I need to make a sticky?
As the weather gets cold the coolant pump motor gets noisy...sometimes it'll even sound like it's 'stuttering'...but unless and until it makes a terrible loud noise or quits working completely there's nothing to be done.

dogfriend · 10-09-2007, 11:15 AM

I noticed that the sound of the coolent pump has changed in the last couple of weeks (as the outside temp has dropped). Mixed in with the other boot up noises, it sounds like something in a bad science fiction movie. :P

narf · 10-09-2007, 11:19 AM

There are lots of reports on this forum of coolant transfer pumps failing. It begins by making a howling noise which gets worse over time. It seems to make more noise when cold. I'd guess it's a bearing failing. My first Prius got noisy at about 30,000 miles. My current Prius is beginning to howl at 15,000. (I'd hoped they would have come up with an upgraded design by now)

Correct me if I'm wrong, but I think a total failure of the transfer pump will throw a code, but since it doesn't prevent coolant flow (there is a traditional coolant pump) it won't prevent use of the car.

dmb40 · 10-09-2007, 12:33 PM

Thank you for the replies. Any advice on whether the possible failing of this pump should be covered by Toyota's warranty? Might they agree to replace it before it fails if so? It does sound like a overspec clearance in a pump drive. My car has about 13,500 miles. The weather is still 70-80 here in Santa Barbara.

kettledrum · 10-09-2007, 01:06 PM

Dave,

Have you seen this thred here?

http://priuschat.com/forums/prius-ma...power-off.html

The third post has a .wav file. Does your car sound like that? That's the sound of the bad coolant transfer pump according to the experts here.

I'm hoping mine will last until my 15k service, which is still 2,500 miles away.

dogfriend · 10-09-2007, 01:50 PM

Mine sounds like the .wav file.

dmb40 · 10-09-2007, 02:22 PM

<div class='quotetop'>QUOTE(kettledrum @ Oct 9 2007, 10:06 AM) [snapback]523157[/snapback]</div>

Quote:

Dave,

Have you seen this thread here?

The third post has a .wav file. Does your car sound like that? That's the sound of the bad coolant transfer pump according to the experts here.
I'm hoping mine will last until my 15k service, which is still 2,500 miles away.
[/b]

That is it. Thanks. I will see what Toyota offers...

Dave

kettledrum · 10-09-2007, 03:56 PM

Evan,

Would you characterize the noise in that .wav file as the "terrible loud noise" you were referring to?

10-09-2007, 11:19 AM	#5
narf Senior Member Join Date: Mar 2005 Location: Colorado Posts: 546 My Car: 2008 Prius Model: Package: #6 Touring Thanks: 0 Thanked 0 Times in 0 Posts Friends: 0	There are lots of reports on this forum of coolant transfer pumps failing. It begins by making a howling noise which gets worse over time. It seems to make more noise when cold. I'd guess it's a bearing failing. My first Prius got noisy at about 30,000 miles. My current Prius is beginning to howl at 15,000. (I'd hoped they would have come up with an upgraded design by now) Correct me if I'm wrong, but I think a total failure of the transfer pump will throw a code, but since it doesn't prevent coolant flow (there is a traditional coolant pump) it won't prevent use of the car. __________________

10-09-2007, 01:06 PM	#7
kettledrum Senior Member Join Date: Aug 2004 Location: Indianapolis, IN Posts: 178 My Car: 2006 Prius Model: Package: #4 Thanks: 6 Thanked 2 Times in 2 Posts Friends: 0	Dave, Have you seen this thred here? http://priuschat.com/forums/prius-ma...power-off.html The third post has a .wav file. Does your car sound like that? That's the sound of the bad coolant transfer pump according to the experts here. I'm hoping mine will last until my 15k service, which is still 2,500 miles away. Last edited by kettledrum; 06-21-2008 at 02:05 PM. Reason: fixing link from new url names

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10-09-2007, 06:16 AM	#1
dmb40 Junior Member Join Date: Mar 2007 Posts: 16 My Car: Model: Package: Thanks: 0 Thanked 0 Times in 0 Posts Friends: 0	My 2007 has always booted up with an electric motor running in the left front of the engine compartment before the ICE starts. Recently it sounds quite different, almost like it is cavitating. All the fluid resoviors are full. Can you tell me what that pump/motor noise is and how to check it out? Thanks, Dave

10-09-2007, 08:55 AM	#2
qbee42 Senior Member Join Date: Mar 2006 Location: Northern Michigan Posts: 10,487 My Car: 2006 Prius Model: Package: #7 Thanks: 95 Thanked 392 Times in 290 Posts Friends: 10	Has it been cooler outside? The coolant transfer pump often makes a bit more noise when it is cold. The pump you are hearing transfers engine coolant to and from a thermos bottle so as to save the heat in the liquid as long as possible. Tom

10-09-2007, 09:27 AM	#3
efusco Troll Slayer Join Date: Nov 2003 Location: Nixa, MO Posts: 17,250 My Car: 2004 Prius Model: Package: #9 Thanks: 50 Thanked 261 Times in 157 Posts Friends: 37	This is probably the 4th 'report' of this so far this season...perhaps I need to make a sticky? As the weather gets cold the coolant pump motor gets noisy...sometimes it'll even sound like it's 'stuttering'...but unless and until it makes a terrible loud noise or quits working completely there's nothing to be done.

10-09-2007, 11:15 AM	#4
dogfriend Human - Animal Hybrid Join Date: Feb 2007 Location: Carmichael, CA Posts: 4,967 My Car: 2007 Prius Model: Package: #6 Thanks: 288 Thanked 175 Times in 147 Posts Friends: 11	I noticed that the sound of the coolent pump has changed in the last couple of weeks (as the outside temp has dropped). Mixed in with the other boot up noises, it sounds like something in a bad science fiction movie. :P

10-09-2007, 12:33 PM	#6
dmb40 Junior Member Join Date: Mar 2007 Posts: 16 My Car: Model: Package: Thanks: 0 Thanked 0 Times in 0 Posts Friends: 0	Thank you for the replies. Any advice on whether the possible failing of this pump should be covered by Toyota's warranty? Might they agree to replace it before it fails if so? It does sound like a overspec clearance in a pump drive. My car has about 13,500 miles. The weather is still 70-80 here in Santa Barbara.

10-09-2007, 01:50 PM	#8
dogfriend Human - Animal Hybrid Join Date: Feb 2007 Location: Carmichael, CA Posts: 4,967 My Car: 2007 Prius Model: Package: #6 Thanks: 288 Thanked 175 Times in 147 Posts Friends: 11	Mine sounds like the .wav file.

10-09-2007, 03:56 PM	#10
kettledrum Senior Member Join Date: Aug 2004 Location: Indianapolis, IN Posts: 178 My Car: 2006 Prius Model: Package: #4 Thanks: 6 Thanked 2 Times in 2 Posts Friends: 0	Evan, Would you characterize the noise in that .wav file as the "terrible loud noise" you were referring to?