Odd vibration after coming to a stop

I am about 99% sure it is the AC compressor running. I notice it through the brake pedal on my car too. I don't use AC that often, so it stands out to me.

 

is it happening before and after the engine shuts off?

 

It is definitely the AC Compressor. Mine does the same thing. Next time you feel it just turn the AC off and see if it stops.

 

I will have to agree with the Air Compressor explanation. Living in Fort Worth I feel it every time I get in the car on a hot sunny day. The Prius can bring the A/C compressor to a very high RPM level when it is not on ECO mode and it is trying to cool down the car on a hot summer day. I only feel it while the compressor is giving it all it has. Once the cabin temperature starts to go down it disappears. Next time it happens turn ECO mode on and see if it stops; you could also try and increase the set temperature to force the compressor to slow down. I always use the Auto setting so I am completely used to it. I rather have the vibration than no A/C.

 

Likely this. The compressor runs based on load (how hot it is in the cabin and what temperature you set the system at). Every time it's HOT, I hear a grinding noise from under the hood and sometimes feel it through the brake pedal, and I can tell it's the compressor going full bore.

I'm somewhat disconcerted that it's so noisy when running at full load. Normal A/C compressors run at a set rate and are relatively quiet. My guess is that the electric motor running the compressor

 

i wonder why liyah didn't notice it in her first prius, maybe gen 2 a/c was different?

 

I definitely notice the A/C compressor in the Gen 3 more than the Gen 2. But, I've not noticed vibration, just a simple spinning sound. Leave your car in Ready with the A/C on, and get out of the car (or maybe just roll down the window in an otherwise quiet setting) and you'll hear the A/C cycling on/off every few seconds. At least this is what mine does. Whirring sound yes, vibration no.

 

yes, i can hear mine as well. liyah, can you hear yours?

 

Speaking of that, how about the Verizon guy who used to say "can you hear me now" leaves Verizon for Sprint and now says "can you hear this".

 

I'm glad to have found this thread, as I'm in exactly the same situation. My previous Prius (2005) never did this, and my current one (2011) just started a month ago. I just had the car in for service this morning, and the dealer found no issues with the A/C. It sounds like it isn't anything other than a very minor annoyance.