I have a 2013 Prius that I have had for a bit over 2 years now. Over the past 6 months or so, I have noticed something strange start to happen. It seems to occur more often after it has been sitting for a few days without being driven, but I don't think that's a hard and fast rule. After I start it, take off the emergency brake, and put it in drive, the Prius doesn’t start moving forward by itself. I have to press the gas pedal, which I do as lightly as possible, and eventually I hear a mechanical clunking noise from somewhere underneath the car and it starts moving normally. This does not appear to cause any any other issues, and does not happen again until the car is parked for a while. Does anyone have any idea as to what the problem might be? I was thinking that it could be something to do with the parking brake sticking, but I really have no clue. Thank you! Ben
The brake pads are stuck onto the rear rotors due to a layer of surface rust that has formed on the rotor surface. It's entirely normal, especially when driven through rain or over wet roads. Also, after morning dew has caused the rotors to form that film of rust. Posted via the PriusChat mobile app.
Ah, that makes complete sense! Thank you for the answer, I am very glad to hear that it's something normal.
Next time you're in the similar situation try NOT setting the parking brake. And then see if you have the same clucking noise, and if the car will move with pressing the throttle. You could also try reversing first, and listen for the noise.
I had that in spades, on Friday: the car had been hosed down to clean off salt, about 4~5 day previous. Started it up, put in reverse, foot off the brake, and nothing happened. Gave a little gas and it broke loose with a bit of protest, a quadruple, resonant, p'toing, and away I went. Every time I touched the brakes for the next block you could hear a scrubbing sound, as the surface rust got ground down.
