New (to me) Prius and unusual sound

Hello,

I just purchased a used, 2008 with 130K miles on it. I had no opportunity to take it to a dealer to be inspected, however I do all my own work and the standard things checked on a vehicle I did. It has an extensive history of maintenance throughout it's life according to the Toyota owner's site, however there are questions about fluid changes (coolants, brake flush, trans drain and fill), though both the engine and hybrid water pumps were both replaced within the past 5k or so miles. I would hope that the coolant was exchanged. It looks nice and pink. I drove it extensively before purchasing and found no issues other than a few rattles. I spent $2000 or so less than comparables and even more than that off NADA, so I'm comfortable spending some money for repairs.

The past couple of days my wife and I have noticed that occasionally on startup, or when pressing the brake pedal especially hard when stopped (such as changing seating positions), there's a quick squeak or two. I would normally suspect the ABS pump, but where it only squeaks once or twice I'm not sure. My previous vehicle had a bad bearing in it's interior fan and on the first revolution or two as it started sounded almost exactly the same. I would expect the ABS pump to run more than one or two revolutions. As stated earlier, I don't see any entries for a brake flush, so I was planning on that. I don't want to pay to have it done only to have to pay again to have the pump replaced. I'm aware that I cannot bleed the brakes myself (unfortunate). Has anyone experienced issues like this? Also, though I've seen it mentioned many times, I've never seen any actual costs of the dealer flush.

I'm new to this Prius and to ownership, but I am very familiar with them having driven my father-in-law's quite a bit as well as extensive research.

 

Thanks for the replies. Nice to be on an active enthusiast forum again

 

Update to my issue posted long ago. It has become more frequent. It is definitely heard outside and inside the vehicle. I'm 99% sure it is what I hear referred to as brake "bark". It only does it when the system is using the conventional brakes. It's so bad that we put it in part so we can let off the pedal at lights. It's now also to the point where I can feel minor surges that correspond to the noise when under 5 MPH. I bought mini vci and successfully ran a 32 ounce bottle of new brake fluid through the system. I could see no air bubbles in any of lines. It did seem to briefly reduce the noise, but it's back and worse than ever. I suspect that my ABS pump/actuator needs to be replaced. I can't see where anyone has done this themselves. On any other car, I would never hesitate to do any job. As stated above, I have the mini vci to take care of the bleeding, but I am unaware of the procedures. Has anyone performed this themselves? If I need to, is the standard subscription to Toyota's tech site enough to get me what I need? Any other thoughts before I purchase a used one and dive in?

 

I will definitely try to capture the process when I do it. My issue is beyond noise at this point. As it starts "barking" when the friction brakes take over, you can feel a surge in the vehicle with each noise. If it were just the noise, it may be passable, but with my wife driving it 90% of the time, I don't feel comfortable that it's continued to get worse to the point where it is affecting braking performance. Additionally, I've had 4 occurrences where I've received ready, but apparently the accumulator was bled down and the vehicle moved about 2 feet after shifting into gear before the brakes stopped it (all the while with my foot firmly planted on the brake). To go along with that behavior I've noticed that the pump is running a lot more than I think it should - very often starting while I am moving not having applied brakes recently.