rattling sound when accelerating and decelarating

smkimm · 03-26-2005, 09:41 AM

our new 2005 prius makes a little 'rattling' sound whenever we slightly starting to stop or start, then it goes aways. it's like the sound of thin metal band hitting a cog or something rather constantly for 2-3 seconds.
it anyone having similar problems?

mtc1234 · 03-26-2005, 11:15 AM

Any particular direction it seems to be coming from? I have a little rattle that seems to be associated with the drivers side tweeter (or there abouts).

smkimm · 03-26-2005, 11:56 AM

it seems to be coming from front side of the driver's seat; from the engine side perhaps? it sounds as if the gears are adjusting themselves or some sorts. . .

200Volts · 03-30-2005, 01:14 AM

Mine does the same thing 92004 with 34k). The dealer said this is the brake accumulator charging itself for the antilock system.
With the car in park, pump the pedal about 6 times with moderate to light pressure and see if you can make the noise start.
Mine has gotten much louder with time. I just drove a 2005 and it was almost silent (3k miles).

smkimm · 03-30-2005, 08:42 AM

I think you are right that it's coming from the brake system. does anyone know if this is something to be fixed, or should be fixed under the warranty??

DanMan32 · 03-30-2005, 10:04 AM

That's a normal sound of the brake pressure accumulator increasing hydraulic pressure. Think of it as a hydraulic compressor (which it is). Compressors are noisy aren't they? Prius is no different.

03-26-2005, 09:41 AM	#1
smkimm Join Date: Mar 2005 Posts: 3 My Car: Model: Package: Thanks: 0 Thanked 0 Times in 0 Posts Friends: 0	rattling sound when accelerating and decelarating our new 2005 prius makes a little 'rattling' sound whenever we slightly starting to stop or start, then it goes aways. it's like the sound of thin metal band hitting a cog or something rather constantly for 2-3 seconds. it anyone having similar problems?

03-26-2005, 11:15 AM	#2
mtc1234 Member Join Date: Mar 2005 Location: Laurel, MD Posts: 39 My Car: Model: Package: Thanks: 0 Thanked 0 Times in 0 Posts Friends: 0	Re: rattling sound when accelerating and decelarating Any particular direction it seems to be coming from? I have a little rattle that seems to be associated with the drivers side tweeter (or there abouts).

03-26-2005, 11:56 AM	#3
smkimm Join Date: Mar 2005 Posts: 3 My Car: Model: Package: Thanks: 0 Thanked 0 Times in 0 Posts Friends: 0	Re: rattling sound when accelerating and decelarating it seems to be coming from front side of the driver's seat; from the engine side perhaps? it sounds as if the gears are adjusting themselves or some sorts. . .

03-30-2005, 08:42 AM	#5
smkimm Join Date: Mar 2005 Posts: 3 My Car: Model: Package: Thanks: 0 Thanked 0 Times in 0 Posts Friends: 0	Re: rattling sound when accelerating and decelarating I think you are right that it's coming from the brake system. does anyone know if this is something to be fixed, or should be fixed under the warranty??

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03-30-2005, 01:14 AM	#4
200Volts Senior Member Join Date: Nov 2004 Location: Northern CA Posts: 362 My Car: Model: Package: Thanks: 0 Thanked 0 Times in 0 Posts Friends: 0	Mine does the same thing 92004 with 34k). The dealer said this is the brake accumulator charging itself for the antilock system. With the car in park, pump the pedal about 6 times with moderate to light pressure and see if you can make the noise start. Mine has gotten much louder with time. I just drove a 2005 and it was almost silent (3k miles).

03-30-2005, 10:04 AM	#6
DanMan32 Join Date: Aug 2004 Location: Tampa Bay, FL Posts: 3,775 My Car: Model: Package: Thanks: 0 Thanked 0 Times in 0 Posts Friends: 0	That's a normal sound of the brake pressure accumulator increasing hydraulic pressure. Think of it as a hydraulic compressor (which it is). Compressors are noisy aren't they? Prius is no different.