My 2012 is leaking antifreeze from the radiator area and burning coolant! Overheating light began to flicker for a couple of secs after going up a hill, and discovered low coolant. Topped up by local (limited expertise) shop who obviously didn't check for leaks. About a week later, engine seemed to loose power so brought to different shop who figured out leaks. They suspect head gaskets (though say they've never actually had to change in other Prius' they see). Issue is - it's a big risk to invest when the engine might be a goner. I'm devastated! We LOVE this car and wish we'd found a better mechanic to take care of this past few years. ADVICE sought please..... 1. Other possibilities? 2. Go ahead with head gasket change (though still need to find source of radiator leak). 3. Say goodbye and sell / donate and take the tax credit?
Your engine fault codes are inactive, but they are worth paying attention to. P3190 and P3191 indicate problems with starting. Your temperature sensor shows very high values. Its circuit may be damaged and shorted. P0117 Short in engine coolant temperature sensor circuit for 0.5 seconds (1 trip detection logic) If there is a short circuit, the tester indicates 140°C (284°F) or more. Of course, it is necessary to deal with a coolant leak, but you won’t be able to do it remotely. You need to either inspect the possible leak sites yourself or use a repair service specialist for this.
This is not the car to be thinking you're holding a keeper. This ain't the one neither is the generation 4 generally speaking so if you can't move to a generation 5 which is like a $20,000 plus car or do something else I don't know what you're going to do but this generally to me wouldn't be it I've put two of these out to pasture very quickly for the same problem others have fixed the mess I don't know how long there's are lasting but this isn't the one to be experimenting with that . Unless you have reasonable disposable income that you can afford to piss away so if you have all that you're good to go tell the shop to get to urinating. If not you need to be figuring out how you the wife and kids are going to get from A to B if you're a one car family. These are real things fixing this Prius and keeping it because somebody thinks they might ought to think again The track record and the numbers generally aren't with you so before you pull the trigger on a mechanic shop wherever they are and wherever you are you better do some serious soul searching especially if money and things like that can creep up and become an issue because this is one that will do that for you very quickly That's been my experience and I've been with Toyota for 47 years and the generation 3 Prius is the one that did it for us put Toyota in the Chevrolet category basically oh well so we just don't own anything like that 2010 is planned obsolescence executed very well If you can't afford that you should stay away from it Toyota and Chevrolet and stalantis they need you to be buying a vehicle every three to five end of discussion If you can't do that you ain't worth the crap to them and that discussion in a nutshell they are proving this almost weekly now some people can get a grip and catch on many cannot.
They can’t have much gen 3 experience lol. what’s the miles on it? have you had it since new, and if not: at what miles did you acquire it? if it’s around 150k miles, never had water pump and thermostat replacement, nor Exhaust Gas Recirculation system cleaning, the two contenders for culprit would be the pump and head gasket. Likely both.
Another request for the miles on the car. My guess without looking at your car is that the engine water pump is going bad, which is causing insufficient coolant flow through the engine. This causes the engine to overheat, and then the coolant boils and is forced past the black cap on the plastic reservoir on the passenger side. Look for evidence of coolant or dried coolant near the reservoir. Do not drive the car at highway speeds or up large hills until the water pump is replaced. An OEM pump is preferred because cheap aftermarket pumps only last about a year. Engine water pumps going bad is a common problem on the Gen 3 Prius, usually between 150k and 200k miles. Edit: The P0117 code indicates that the engine got extremely hot. I believe that replacing the water pump will fix the car in the short term, but the headgasket will start leaking within the next year or so because the engine was severely overheated.
P0117 indicates a temperature reading so high the car wonders if it might be a sensor problem, but in cases of coolant loss one also has to consider the possibility that it's not.
Were there any severe morning rattles prior to the overheating? This symptom of early head gasket failures is important and is often overlooked until the head gasket is more advanced and coolant is lost. A lot depends on your financial situation and willingness to live with a lower reliability car into the future. This forum is full of diy'ers who love a challenge. These cars are very challenging in their old age. Given you are listed as living in NYC, I doubt there is a value oriented independent hybrid shop to properly handle the issues in a cost effective manner. Most regular shops don't want to work on hybrids due to their complexity. As suggested above, any shop who has not done a gen3 Prius head gasket simply rejects the work. On top of that, Prius Gen3s (2010-15 and v wagons 2012-17) have many expensive reliability issues as they age. Engine, brake system, hybrid battery and inverters are all in that category. The cars often burn oil which is enough of a problem in itself to warrant engine replacement or to justify selling it. If this is actually a radiator leak FOR SURE I "might" fix it just to see if other damage was done. A radiator from a salvaged Prius would be my choice as they rarely leak. Which makes me wonder if your information could be flawed. Often an antifreeze release is actually from the passenger side reservoir cap which has a pressure relief toward the back corner. A normal shop could handle swapping the radiator but don't expect a complete fix as head gasket fails are common. Yes an engine in a NYC area shop might be $10k to do it right. Normally they would install a new short block and rebuilt head along with cleaned up reused parts. In other parts of the country it might be $5k to install a rebuilt engine. Some would go with a used in Japan "JDM" engine for less than $5k installed. I would not consider a used salvage yard engine.
Get a second opinion; preferability a Prius specialty shop. Since your losing coolant; burnt and/or leaking, the radiator replacement may just be a "value added service". Not leaking, shop trying to cover their bases. The plastic coolant overflow jars do fracture and leak when exposed to excessive heat. Those radiators usually don't leak, but they do burp from overheating. We can't see that over the internet. @rjparker has the most likely diagnosis - electronic water pump and thermostat. Coolant is boiling out due to water pump circulation not keeping up with ECU demand. This may also cause a head-gasket failure; but you need to deal with one problem at a time because it may solve other problems down the line. The water pump & thermostat replacement would be the most likely cure. If the head gasket issue persist, you'll have to decide to fix, sell, or trade it. Unfortunately; poor timing...... Good Luck.....
Hybrid battery replaced 2021 12V and pump replaced 2022 Cat converter stolen around this time, and perhaps that destabilized (or 'repair' process). YEP - agreed. Just unsure of cause. Will post entire 'diagnosis' + videos.
Forget about the radiator leak unless you're going to fix the car you'll need a new one they're telling you you're burning coolant so that means it's getting through the engine so that's generally head head gasket seal and all of that so here you are choices choice is choices
Agree - obvious burning coolant (white smoke) is a head gasket. "NOTED EXCESSIVE AIR IN ENGINE COOLING SYSTEM. PUT VEHICLE INTO MAINTENANCE MODE AND BLEED COOLING SYSTEM. NOTED VEHICLE IS BURNING ANTIFREEZE (SEE ATTACHED VIDEO), LIKELY HEAD GASKET PROBLEM."
Looks like your down to very expensive repairs - so your down to repair, mechanic's special sale, or trade it in.
