Loud grinding noise when accelerating hard

[Christopher Dale]

My 2021 Yaris Hybrid has covered just over 8000 miles and drives well and quietly normally. On one occasion however it gave out a loud grinding noise when accelerating hard. The noise stopped as soon as I took my foot off the accelerator. Yesterday I had a similar experience driving up a very steep hill - everything was fine until I tried to increase the speed which produced the grinding crunching sound until I eased off the pedal whereupon the car proceeded at its sedate pace to the top of the hill. It's almost as though the car has a built in warning if I try to push it too hard with my big feet! I have taken the hint but I wonder if anyone else has had a similar experience.

[Cyker]

If you'd gotten a hybrid system error I'd have guessed it was the damper plate slipping, but since you didn't I'm not sure what it could be!

I drive mine pretty hard fairly regularly and haven't come across such noises or behaviour...

I wonder if something has come loose and is rubbing on the brake discs or drive shafts or something when you're accelerating hard enough to generate some g-force...?

Any chance you can record the sound...?

[Derek.w]

I drive up/down steep hills all the time without any issues in my mk4.

Open your window to help locate noise also have a quick look under the car for loose heat shield resting on the exhaust.

[Christopher Dale]

Thanks. I will investigate further! 

[Mikw]

Any follow up on this?

Mine's done 26000 miles now and it did this during a long drive last night, only once but it was just before i returned home going up hill. It's rather ruined a great night.

[TonyHSD]

Wheel spin perhaps, if it happens at speed the stability control may be activated and to produce similar grinding noises to abs activation when braking on slippery surfaces. Just another reason eventually.
For any unusual or abnormal noises or behaviour, a good practice is to wait for the car to see if it will happen again and in what circumstances and make a note than compare with others cars or look for answers online. It could be something typical for these cars. 👍

[YarisHybrid2016]

I drive my car pretty hard, but so far, no weird noises.

ABS can sometimes make grate-y sounds. Think when the PKBA hits the brakes getting close to a wall. BRRRRRRRRRRRRRRRRR!

[anchorman]

It’s a thing.  Contact your dealer, they’ll fit an upgraded damper under warranty.  

[Cyker]

From experience, that doesn't really produce a prominent grinding sound, and they'll only do a replacement if the Hybrid System Malfunction message comes up and a specific code is read off the diagnostics - I asked them about this damper replacement, as I experienced this, but because they cleared the code and didn't record it, they say they can't do anything about it even tho' they know it happened, as they need to send the proof to Toyota so it can be done under warranty and can't do that unless it happens again.

I'm in two minds about it, as it hasn't happened again since, and I feel I'm better off as the replacement procedure has a long lead time and is extremely invasive and I frankly don't trust them to do it without smegging something up (e.g. sealing the drive units back up properly)