Clank/thump/spung! about a minute after I turn off the car

I hear some clunks and whirs on ours, just after shut down. Believe it's normal. There's also some similar noises, hours after shutdown, coming from the back somewhere, connected to the gas tank somehow?

And when you first open drivers door when it's sat for a while, you hear about 10 seconds of whirring, as the brake system pressurizes. If you raise the hood: you can actually see the brake fluid reservoir level dropping as that happens.

 

It's the car doing its normal brake self-exam. If you listen very closely between the thump and the spung, you might hear a very faint whoosh of brake fluid.

-Chap

 

Prii make many different sounds after shut down. I sometimes wonder if mine aren't talking to each other when parked side by side in the garage. I've been working in the garage long after shutting down the Gen III and it is still making noises. Always fun when "non-Prius" people catch a ride with you - you come to a stop at the light, the ICE shuts down, but the car keeps making noises.

 

First time I heard the hours later sound, I happened to have the car jacked up, was looking at the underside. Scared me some.

 

Disturbed your nap with a nightmare?

 

I'm experiencing something similar to what OP describes, but have have observed it happens a few minutes after the ICE shuts off - happened in traffic recently where I was crawling on electric only.

Both the sound and the time it happens at are not consistent, so I'm not bothered waiting 5 minutes over the hood to get a better indication as to where it comes from. And then do it again to get more specific. Some times it's loud though!

If it's the brakes self test, do we need to clean/lubricate/replace something?

 

Nope, totally routine test. If it detects anything you need to know about, it'll say so with a diagnostic code. That's what's nice about self-tests.

Nothing to say you shouldn't keep checking your slide pins and rubber boots every 30,000 miles or so, just to keep everything humming. But that's just what you'd do anyway.

-Chap