Inverter 2010 233,000mi

Usually an overheating will cause car to stall.pumps are around 160, see if you can find someone cheaper

 

If you do have to drive it any before the pump gets replaced, it would be handy to have some OBD-II tool or phone app plugged in and watch the coolant temperature.

In fact, if it stalls again while you are doing that, please post the temperature at which it stalls.

There was a recent thread here where I tried to do that in the driveway, based on a note in the Repair Manual that it will stop the engine at 105 ℃ if there is already a water-pump trouble code logged. But there is one way the pump can fail that 2010s didn't have a trouble code for (2011 added one), so in a 2010 if the pump fails that particular way, the ECU doesn't necessarily know it.

In my driveway, with a working water pump and no trouble code, I was able to run the temperature up past 105 ℃ (by disabling the fans) and the engine did not shut down. Apparently when the pump isn't already suspect, the limit is higher. I just didn't find out what the higher limit is, because I went up to 107 ℃ and then chickened out.

So if another stall happens to you, it would be helpful to post the temperature so we know what that limit is. However, I would not advise deliberately pushing the temperature just to find out. (Overheating is especially dangerous when it happens because of a pump problem, because the coolant isn't circulating so the engine isn't even overheating evenly.)

 

Consider buying another car.

The Gen-3 Prius also has an issue where the EGR system clogs, usually at a mileage less than yours. This clogging also could lead to overheating and head gasket failure, a major repair.

You could get the water pump replaced, and hope for the best, but you should also address the EGR system. The EGR cleaning (or component replacement) is labor intensive ($$). If you have the tools and a place to do it, the water pump simply bolts on to the engine. The EGR system takes more patience to do yourself, but most folks here have DIY-ed it.

Have you had to add engine coolant, or have you ever experienced noticeable shudder shortly after starting the car?

 

You might also consider an easy, non-invasive step, such as pulling up the value from the car's last EGR flow test, as part of deciding what kinds of work to prioritize.

It is also (comparatively) easy to get just the intake manifold off, and clean its separate EGR passages into the four intake ports. That's the only part of the EGR system that is downstream of the MAP sensor and therefore 'invisible' to the computer that monitors and controls the EGR flow, and if those passages are clogged to different extents, that could mean that even when the flow overall is sensed as sufficient, it might not be right in all cylinders.

If removing the manifold, I'd recommend new gaskets (they're cheap). They are the (somewhat) reusable thick rubber kind, which you can get away with reusing if, say, you have another reason to take the manifold off again in the future, but one that's been there since the factory is probably somewhat cooked and flattened.

 

EGR (and intake) cleaning is a good head gasket preservation tactic, but if you're losing coolant the head gasket's likely already failing. A leak-down test could confirm. I would remedy the head gasket and immediately thereafter do the EGR/intake cleaning, and consider a oil catch can too.

Info on EGR cleaning, plus oil catch can install:

Bad Flywheel | PriusChat

Head gasket rebuild, bundle of repair manual excerpts:

Blown Head gasket rebuild....@297k | Page 15 | PriusChat

 

Over the next days, you're sure to get many opinions on what work you should have performed. Read and analyze them.

My thinking is that if it were my car, I wouldn't trust it for a long, important trip, since it could break down. You haven't spent big $ on repairs yet, so you could apply repair funds towards a used Corolla or Camry, for example.

 

You certainly need to get the water pump fixed as the first order of business. Otherwise it could get much more serious. I trust dealer's advice in cases like this but like others suggest, an independent hybrid experienced mechanic is my first choice if diy is not in the cards.

I would then keep an eagle eye on the passenger side coolant reservoir. It should not use or lose coolant, period end of story. I would tell the mechanic to carefully check for external leaks after the water pump repair, not just at the pump but throughout the car. Coolant is flowing even to the catalytic converter and egr system.

 

I know this thread says "inverter" in the title, but as near as I can see it is just a thread about engine overheating. I'm not positive there is a code for the engine stopping due to overheat. Seems like it would be worth having a code for, but I can't say that I've run across it.

 

I would just replace whichever one needs it. You can usually tell if the inverter pump is working by looking at the fluid in the inverter reservoir while the car is ON (just ON, not READY).