2008 Prius Loss of Power at freeway speeds

Hi all-

Wish I had a better first post to make, but alas, no. I'm in somewhat urgent need of help.

My wife's a couple states over in UT, and is experiencing a loss of power at freeway speeds (~60mph+). Unfortunately, I'm in CA and can't directly help.

The issue: Flooring the gas will cause the engine to rev high, but the car still slows down. I asked her what the battery charge state was when this was happening, she did not know.

The car's been towed to my Mother In Law's mechanic, who I've spoken to on the phone. He can replicate the problem after about 5-10 miles of freeway driving. He also did not know what the battery charge state was when experiencing the issue.

No codes were stored in the computer. The maintenance required light did come on prior to the issue.

He said there was sufficient fluid in the transaxle, and it didn't smell burnt.

This car's got about 134k miles on the clock.

He recommends a replacement of the transaxle with a junkyard unit from a 60k mile car. This will cost $1500 installed, half parts, half labor.

I did not get a warm fuzzy feeling from him that he was overly familiar with hybrids. When asked what he recommended, he replied, "I'd replace the transmission, I'm not sure what else it could be". This feels more like throwing parts and money at the problem than knowingly diagnosing and solving it.

There's also a dealership in the immediate area she's in that we could take the car to for a second opinion.

It seems there's a bunch of issues that could cause this behavior, from battery pack issues/ overheating to coolant not flowing to low fluids to actual transaxle issues.

Would love to get any recommendations you might have. Might end up having to fly her home as she's already a couple days beyond planned on her trip.

Thanks,

Ron

 

Thanks!
I'll reconnect with him and have him check that. Much appreciated!

 

Thanks again. I've got him looking into the inverter pump. I get the sense if that's it, he's competent to change the pump, but yeah, he's in a land of big trucks, not gas sippers.

 

Thanks!

I fear he may be the only game in town, but will look into that specifically. It's a fairly small rural-ish town, but there may be a dealership within striking distance. If so, I'll have my wife get the car there and get a second opinion. If that's not an option, I would absolutely love to take you up on a phone walk-through. If you could send me a PM and let me know what that would entail, I'd appreciate it. Happy to pay your for your time.

RE: getting this to a second opinion: is there any danger of damaging the car by driving it (outside of getting creamed on the highway)? IE: should we abuse our AAA towing benefits or just drive?

Just so frustrating not being directly there to diagnose this myself. I'm not all that well versed in the Prius myself, but I can bulldog a problem like nobody's business

Thanks!

Ron

EDIT: Looks like there's a dealership about 5 miles away from this guy, and it looks accessible via surface streets.

 

Definitely prepared for that. I'd actually budgeted for an HV pack repair or replace when we took possession of this from my mother in law (it's the "Free-us", so far we're only out reg and new tires), so a big repair bill isn't daunting, I just want to throw money at the correct location of the problem

 

Unfortunately, we've not established that, and it's at the garage, so we can't test it at the moment, but I'll include this in my checklist.
Thanks,
Ron

 

Thanks, Eric!

 

Eric, thanks so much for you time on the phone this morning, I really appreciate it!
Hopefully we can get an accurate diagnosis ASAP.
I'd really like to get my wife back home

 

thanks!
By chance, did the UT mechanic reach out to you?

Best,
Ron