2006 Prius died on the freeway???

Nope, but it sounds like these guys are parts throwers.

12 volt battery replacement isn't cheap but $427 is a ripoff. Sure, it's possible there could've been a bad tank of gas, but to replace the tank? What's the cause of the coolant loss?

 

$427 for parts and labor for a 12 volt is still a ripoff. Part should be <$200. (Per New 12v Battery, Part #28800-21171 | Page 3 | PriusChat, it was ~$138 last year, after some weird pricing snafu.) It doesn't take that long for someone who's done it before.

It would be super helpful to post the codes (aka DTCs) that were retrieved. Otherwise, it's just guesses other than the obvious stuff that needs no codes (e.g. no coolant).

 

Do you mean the "head" is blown (as in blown head gasket)?

Also, was it the engine coolant or the inverter coolant that was low?

Lack of engine coolant can definitely cook the heads, cause them to warp and blow the head gasket. I'm not totally familiar with all the warning lights (lucky enough not to have any yet) but I'm pretty sure you should have got a "thermometer" icon along with the master warning light if it was overheating. Did you see anything other than the master warning light?

 

The initial symptome you describe are classic to a failed inverter pump. The system/inverter will run fine when cold/initial 10 minutes or so then the inverter heats up and shuts off (lights everywhere). You turn the car off and let it sit, the inverter cools off and everything is fine until it heats back up and the process repeats.

It seems the car may have also been run with no or little engine coolant at the same time causing a blown head gasket or header gasket (aka exhaust manifold). It is important to know which one is really blown. To me, when you say header, that is the exhaust manifold gasket. That is a problem and a pain to fix but it is not nearly as bad as a "head gasket" blown. If a header gasket is blown, the engine will be very loud but, it should run ok. If its a "head gasket", the oil will appear milky colored (normally but not always) or, the engine will either not run or run rough with low power. Either one is not good but if it is indeed the header gasket, you shouldn't need a whole new engine.

 

Yes I agree. It sounds like they didn't bleed all the air out of the inverter coolant loop or otherwise messed up that pump change in some way. Strange to have a seemingly unrelated overheating issue in the engine at the same time though?

I guess that this thread shows that having a recent "World Class" inspection doesn't necessarily give you the green light to ignore all dash warnings though.

I agree with OP that their "World Class" inspection probably wasn't all that great. Probably neither was their job on the inverter pump replacement.

 

I'll be interested to know what they find out.

BTW. Is it the Toyota dealer or your independent mechanic that's pulling it down?

 

Hmm - if you believe that the dealer tech botched the WORLD CLASS INSPECTION, why are you returning to the same dealer to see what is wrong?

Do you believe that the service department will admit that their tech's action (or lack of action) resulted in a four-digit repair bill?

 

Whoa, I'd see if you can stop them ASAP. There is no need to tear the engine down in my opinion. A simple leak down test would confirm a leaking head gasket in which I would recommend a used replacement if it were coming out of you pocket.

 

Mpap,
(insert big red flag here)
Avi knows what he's talking about.

 

Do I understand it correctly that the dealer checked for external leaks, found none, and then suggested engine tear down to look for internal leaks (there may be other ways to find out as suggested above)?

 

Good Lord, get it away from those idiots and over to someone who knows what they're doing.