2018 Prius in drive, randomly won't move forward. Toyota can't replicate....

Hey all, wanted to make a post here to see if anyone has run across this issue.

I have a 2018 Prius that I bought new (in 2018!). I don't drive it a crazy amount, currently has 58,000 miles on it.

Around August 2021, I had an odd issue. I came to a stop sign and when it was my turn to go, I pushed the accelerator and the car barely moved at all. Like half a foot. The engine revved but the car would not accelerate forward. I managed to pull to the side of the road, put it in park, then back to drive. Still wouldn't move. Turned the car off and back on, then it drove like normal. No error lights came on, no error codes, car always showed in "D". Other than the car not moving, you'd have never known there was an issue.

Called Toyota dealership and they inspected the car the next day. They had it a full day, ran diagnostics, road tested, could not replicate the issue.

So I took it home and it was fine until a couple weeks ago (3 years without the same issue!). Same thing happened. I took it into Toyota, they could not replicate. Unlike last time, the problem has now popped up again 2 weeks later.

This time I did a recording. Again, no error lights of any kind, car stayed in drive but sort of felt like in neutral. THIS time I tried pumping gas pedal, bake pedal, neither did anything. I tried just pushing down on accelerator and it "caught" and felt like it jerked forward/shifted, then it drove forward as usual. Once I came to a stop about 20 yards away, same issue.

I turned the car off for about 60 seconds, started up, and it worked.

One thing that kind of stuck out to me is once I started driving AFTER restarting the car, I kind of noticed a loud vent sound in the right rear. This was aside from the AC that was on. Come to find that this cools/vents one of the batteries.

One other thing of note is that this is in CA and was very hot (100+). However, I've driven the card plenty of times in that type of heat without this issue.

Anyone have any experience or ideas of what this could be? As I said above, the official Toyota service center never heard of the issue and has been unable to replicate the issue twice. Best way I can simply describe it is it feels like the car is in neutral but it's not in neutral. Kind of frustrating overall but hoping I'm just missing some other explanation. Thanks for any feedback or experiences!

 

Thank you both for response. I don't have any pets but car is always parked outside, and it's always hot out.

When I first took it to Toyota 3 years ago, the service tech (prior to looking at the car/testing it) opined that it was likely a battery issue but after looking at it they said the batteries were fine (not sure exactly what they did to confirm). The only plus side of these 2 costs is they charged me nothing since they found no problems.

I'll poke around some on the traction suggestion. Just really confusing to me that the problem disappears for three years and here it is again. Anyhow, thanks again for input