2007 Chirping and Vibration

I just bought a 2007 Prius (278K miles) to be a commuter car and there are a couple of sounds that I need some help determining. On a side note, I was told that one owner prior to the last had replaced the engine and batteries but he didn't know when and I had no way to confirm this was true. It still gets great gas mileage. I filled up yesterday with mostly highway miles driven and it got 58mpg. I have a video that I took but apparently the file is too large to upload. Instead, I uploaded it to YouTube.

1st Noise- Chirping
At first I thought the chirping sound was maybe a bad belt or pulley but I am beginning to wonder if it is something else. It seems to be worse when I put a load on the engine (like accelerating from a complete stop) but it can be heard even at normal cruising when the engine is on. When the engine shuts off and the car is still in motion then the sound goes away.

2nd Noise- Loud Vibration
This noise can be heard when the engine is on and the gas is feathered. It goes away when the pedal is fully released and the engine shuts off, even when the car is in motion. If I give the car more gas, the chirping is still present but the vibration goes away. I do have a check engine light on for a P0420 Catalyst System Below Efficiency but I don't believe that is related to the sound. It is hard to tell from the video but it is extremely loud (almost like I have a subwoofer in the car). While looking at the screen, it seems to be worse when the engine is feeding to the electric motor and the wheels but not while the electric motor is feeding to the wheels at the same time as the engine.

I would greatly appreciate any help I can get!

 

Thank you for that feedback, I appreciate it! I will definitely do that. I'm not sure when it was changed last, so it might be good to get that done anyways so I know that it is not going to be a problem later. That would be great if that solved my problem, too!

 

Thanks! I had it looked at my friends shop today and he said the belt was pretty worn and needs to be replaced. Unfortunately, he's out a couple weeks but I'm going to have him replace the pulley, too, so I know that everything is new.

 

He thinks the chirping is the belt and the vibration might have something to do with the electric motor. He's not as familiar with hybrids so he's not 100% sure.

 

Absolutely, it definitely takes some getting used to. It's always a challenge buying a used car and evaluating where you're at with the maintenance, too.

 

Thats a good idea! Thanks for letting me know and for sending the links to the manuals, I appreciate it!

 

I wanted to provide an update on where I am at. I went ahead and replaced the belt and tensioner pulley and the chirping is still there! Last night I pulled the belt back off to see if the noise would go away (thinking it might be the water pump) and the noise is still there! If it isn't related to the belt, what could it be? It's not the brakes because the sound is only present when I'm moving and the engine is on. While driving, once I let off the gas and the engine shuts off, the wheels feed to the electric motor, and the sound goes away. I could really use some help on this.

 

I'm hoping the engine isn't shot, that'd be awful. Unfortunately, the touch screen doesn't work so all I can do is select the auto AC. I had it on when it was cold in the morning and I felt some heat so maybe it adjusts from cold to hot on that setting? It will only make the noise when the engine is on and I'm driving. When it's parked and the engine is on, the engine sounds great.

 

Thanks for letting me know. It definitely is a strange issue. Do you think a bad motor mount could cause this?

 

That's what I was thinking. You would think that if it were the electric motor that it would chirp when the engine is off and the wheels are feeding the electric motor to charge the batteries, right? Fingers crossed that's what it is! I hope I'll know more when I take it in on Friday.