Whirling Noise from engine area

Hard to say. I had a whirling noise and they fixed this under a recall for the brake actuator. Check w/ your dealer to make sure this noise isn't due to the brake actuator as I know they were having trouble w/ this.

As an fyi, my noise only occurred in very cold temperatures. After they fixed the brake actuator it kept occurring. They later determined it was the radio and replaced that. Since it's not been very cold since then, I'm not yet sure if the noise will occur again. Best thing is to take it in to the dealer, document a visit for the noise and see what they say. If it's a problem later, it's on record that you brought it in under the warranty period.

 

<div class='quotetop'>QUOTE(ScottJayhawk @ Oct 31 2007, 01:20 PM) [snapback]533089[/snapback]</div>

Do a Search for "odd thermos noise" and I think the result might explain what you are hearing.
Gary

 

Hi ScotJayhawk,

If the noise is asociated with braking and changes in pitch as you slow down, then thats is the Motor Generators (MG's) under load as they are used to slow the car.

If its a short bruuup type sound, its probably the brake system hydraulic pump. It occaisionally, and not neccassarily in synchrony with brake pedal usage, pumps up the pressure in the brake system accumulator.

If its more of a screech, and occurs on vehicle startup, its probably related to the engine coolant storage pump (or watever they call it). This is an electric pump that pumps coolant from the engine to the thermos (on shut down) and back (on startup). The screeching occurs in colder weather prior to failure. Although Efusco (Evan) will tell you its fine until it gets very loud. I have been lucky to not hear it on my car.

 

It's the automatic Squirrel Twirler.

 

It's the brake accumulator pump. The Prius has electric power brakes, so it uses a small pump to build brake pressure. It does this because the engine does not run constantly as it does on ordinary cars. The brake accumulator pump will run once every three times or so when you press the brake. It's completely normal, unless it's running all of the time, or running when you are not braking.

Tom

 

this thread came up while i was searching for a similar sound that i started noticing...

check out this thread: http://priuschat.com/index.php?showtopic=3...mp;#entry533870

not sure if you all are talking about the same sound as discussed above, but it definitely sounds possible. the things in common: "whirling" or "spinning sound", "brake related", and "thought it was the radio/CD player"...the sound isn't like a "Squeak" which makes me think it's not the brake accumulator...but i could be wrong. anyways, i'll keep an eye out on this thread. Thanks, FJ.

 

The brake accumulator pump noise is more of a buzzing-clicking sound, "Badadadada", and lasts about as long as it takes to say the quote above. It's a little more of a rattle or buzz than what I have spelled out, but I don't know how to do it phonetically. The sound comes from low left on the drivers side, down in the foot-well area.

Tom