I recently purchased a new 2007 Prius. It now has 11,000 miles and I have a question. When the car is coming to a stop or in gridlock traffic - it makes a sound similar to an egg timer. It's a ticking sound as if you were turning the knob on a minute timer backwards. The dealership told me it was normal and it is the sound it makes when the generator kicks in. I do not recall hearing this in the past. Does anyone know what I am referring to? Thanks for your help.
I think the noise you are hearing is the brake accumulator pump - it is the device that provides pressure in the brake system to activate the brakes. I think the noise is normal, I hear it every once in a while.
<div class='quotetop'>QUOTE(new2meprius @ Jul 4 2007, 07:20 PM) [snapback]473250[/snapback]</div> Where do you hear the noise coming from? I was going to ask a similar question. I hear the same type noise coming from what sounds like under the dash or beside my left foot on the driver's side of the car. I do think I hear it more when I'm breaking. It sounds like something is cycling on for about 3-5 seconds and then goes off.
http://priuschat.com/index.php?showtopic=19832&hl= http://priuschat.com/index.php?s=&show...st&p=305650 http://priuschat.com/index.php?showtopic=3...ake+accumulator http://priuschat.com/index.php?showtopic=12243&hl=
My Prius seems to roll forward when I press the "gas" pedal, and slow down and even STOP when I press the pedal to the left of it... IS THAT NORMAL??!? Enjoy the rides folks! You'll probably hear some other weird noises once in a while. Has anyone made a "strange noises heard in the Prius" thread? If no, someone should, and it should be sticky!
<div class='quotetop'>QUOTE(Ichabod @ Jul 5 2007, 12:25 PM) [snapback]473607[/snapback]</div> If you check the last link I posted above, the thread title is "Is this normal?" and the second post lists the source of 4 weird noises that other cars don't make. :lol:
<div class='quotetop'>QUOTE(dogfriend @ Jul 5 2007, 12:49 AM) [snapback]473321[/snapback]</div> Yep, brake accumulator pump. The Prius can't use engine power for power brakes and steering, since the engine is not always running. The brake accumulator pump supplies power for the hydraulic brakes. You will hear it about every third time you step on the brakes (roughly); the sound will come from the driver's side, somewhere down toward the foot-well. Tom
Hey thanks for the replies. I paid very close attention to the noise today. It does in fact make the sound when I brake, it also makes the sound when I accelerate from a stop. All of this takes place under 25 mpg. especially while city driving (stop and go) It does not happen every time and it sounds like it is coming from the dash. Now it has become a huge annoyance to me. I think your replies are on the right track though, because it does happen around every 3rd or 4th time. Is this something that should be repaired?
<div class='quotetop'>QUOTE(new2meprius @ Jul 5 2007, 08:29 PM) [snapback]473807[/snapback]</div> Just crank up the radio and relax... :lol:
Since we can't actually hear it, we can't be 100% sure that it's normal and not a problem... however, it sounds pretty likely that it's your brake accumulator pump. Instead of getting annoyed by it, think of it as a nice sound that's saving you money on gas since the engine doesn't have to run all the time to power various components.
Its normal.. I worried about the sound for the first 10,000 miles or so until I accepted it was just part of the car... it is sort of a "rattlesnake" or "springy" sound that occurs for about 3-4 seconds when I decelerate or brake after I have been moving for a while... it comes from the front left side of the car sounding like it is in front of my left leg as others have noted.... the fact that we all experience the same sound under similar conditions is enough to indicate to me that this is normal and safe...
<div class='quotetop'>QUOTE(new2meprius @ Jul 5 2007, 11:29 PM) [snapback]473807[/snapback]</div> It's normal. The Prius makes a lot of funny sounds compared to normal cars. Thinks of it as a good thing. Tom
If you want to test out the theory, you can force the brake accumulator pump to go on. Stop the car and put it in 'Park.' Press down on the brake hard about 4 or 5 times. The brake accumulator pump should run for a few seconds. Is that the sound you've been hearing? Great. You're done. If it isn't the sound, then you need to consider something else.
I have the same exact situation. I also have an '07 with about 12,000. It occurs upon braking and acceleration from a stop and it does not occur every time. It seems like I've only been hearing it the past few months. Based on responses to this comment, it sounds like this may be part of the normal braking mechanism but if so, why doesn't everyone hear this?
They do. Mile also does it every single time I turn off the car. Most people take it as normal. This car makes a lot of quirky noises. Unless you see a warning light on your dash, have fun!
The sound that you hear after you turn off the car is most likely the coolant transfer pump... or the gas tank leak pressurizer
