2010 Prius V gas engine shutting off on highway, 12v battery draining, water pump?

Hi everyone,

Over the past two months my Prius has been having intermittent problems. When I am going down the highway the check engine light will come on, then a few minutes later the "check hybrid system" message will display on the screen along with a yellow triangle. At this point, the gas engine will shut off and I will have to pull over to the side of the road. The first time this happened the car would not start again and I had it towed to a dealership. They charged the 12v battery, but the codes reset and they could not diagnose the problem.

After that, the problem would happen intermittently if I was driving it for a while on the highway. However, I would pull over to the side of the road and restart the car, and it would run fine. Although the lights would still be on. After a little while, though, all the indicator lights would shut off. I spoke to the dealer and they told me to bring it in once the lights were on.

I drove it for about a month like that, intended to take it to the dealer once I was near there with all the indicators on. However, once again the problem occurred and the car would not restart. So, I had it towed to the dealer again. Again, they could not diagnose the problem after driving it for an hour or get the problem to reoccur. They claimed the 12v cables were loose and that might have been the issue.

After I got the car back from the dealer the problem again occurred a couple times. I took it to the dealer immediately this morning. The just called me and said that the code came up with the water pump, which they would charge me $850 to fix. However, they said that the code read that the pump reached 221 degrees and are not sure if there is further damage to the engine. I asked what they would buy the car for, and they said $2000 cash or $3000 trade. I punched the car into KBB and received offers from local dealerships up to $6k.

My question is: what should I do? What is the likelihood the engine was damaged? This problem occurred about a dozen times over the last two months. However, I drove it to the dealership fine this morning (about 1/2 an hour away). I'm interested in getting a new Prius Prime, but local inventory is pretty low. And I don't want to risk driving the car between dealerships that have a Prius Prime available because the car seems ready to blow any minute. However, I don't want to throw good money after bad by spending $850 in a water pump only for new issues to come up again soon. The car has 175,000 miles and I have always maintained it well. In fact, I (perhaps stupidly) put brand new shocks, struts and tires on last spring for $3k expecting to drive it for a few more years. Probably would have been good to trade it then before this chip shortage... Also, the battery never died and the engine would always start fine since I installed my last 12v battery. I'm the last one that touched the cables. So, how could the 12v have suddenly started dying because of the water pump?

Thanks for any and all advice. This is sort of a weird situation since I'm worried about driving the car further without a new water pump installed as it could die at any moment. But I need to take it to other dealerships to sell or trade. I wouldn't sell this private party in good conscious without at least replacing the water pump, and even then I'd be reluctant as I know the engine could be damages. The car is filthy at the shop right now and they obviously know it needs a new water pump, I could definitely clean it up and take care of a few scratches and dings to bring the value up.

 

Well, I paid the dealership. I called two other shops and they both quoted about $600. I don't have the time or tools to do it myself, I'm in the middle of a move and need a car. And with rental prices the way they are...

So, I went to a dealership today and got a quote on a 2022 Prius Prime LE. Through Costco I got -$350 off MSRP, however, the dealership put's on an extra $4k in bullshit protective coating stuff (discounted to $3k with Costco). I called a few other dealerships and that sounds like the best deal I'll get.

I drove 3 hours today as the dealership was far and the car ran fan. I haven't noticed it burning any oil. I've watched a few videos on checking and cleaning the EGR as bisco suggested. It seems beyond me at the moment since I haven't even unpacked yet. I'm thinking I'll call a few local shops on Monday and ask if they can check that out. My friend had a Gen3 that blew a piston rod. I've heard that it's a relatively common problem, especially in the 2010s, and that cleaning the EGR and sending an oil sample out to confirm the head gasket is in good health is the solution. Considering the car shut down a bunch of times, twice to point I had to get it towed because it would not restart, I'm worried the gasket is probably damaged and it's just a matter of time. I don't want to throw good money after bad getting the EGR checked and/or cleaned if I'm just going to sell anyway. What is a good price for that?

I'm kind of stuck between just getting the Prime or rolling the dice and doing what I can on this one and waiting for the market to return to normal. However, I'll probably want a Prime as my next car anyway, and the tax rebates are about to run out for Toyota. Ugh, decisions. Any input/advice/abuse would be appreciated. Thanks guys!

 

Thanks for all your advice and everything in your sig line.

Since putting the water pump on I've driven the car about 5 hours on the highway with no issues at all. Now I'm considering whether I just want to roll with the old boy until the chip shortage resolves itself and I can get an EV on PHEV at a decent price. I'm thinking of taking into a mechanic to do a leak-down test to confirm the head gasket is in good condition. And, if it is, just get the EGR cleaning done and roll with it. What do you think about that? It's got 175k miles but I've heard of people getting their Gen3s into the 300ks. I've always done all the dealer recommended maintenance, I am surprised no one ever mentioned an EGR cleaning as that seems to be a common thing that needs to be done at my car's mileage. Just worried about throwing good money after bad on this thing if it's gonna blow. I guess I'll see what the leak-down test reveals and come back here for some more advice. I wish I could do it myself, but I am swamped right now and simply don't have the time.

Thanks again for the advice here!

 

Considering the car shut down so many times because of the water color (twice where it would not restart and had to be towed) my major worry is that some permanent damage to the engine has been done and it's a ticking time bomb no matter what I do...

It's very frustrating since the very first time it happened I had it towed to the shop and they spent 2 days diagnosing it but couldn't come up with anything. Yet as soon as I came to the internet several people were able to diagnose it as likely the water pump among other things. Two diaogs and two different Toyota dealers and nothing could get fixed until I came in with all the lights still on. Beyond frustrating since I'm taking it to Toyota dealerships. Surely this is something they would have dealt with before considering it's a 12 year old version of one of their best selling cars...