Throughout its impressive five-generation run, the Toyota Prius has mostly been a solid, economical car. Not only did it popularize hybrid propulsion in America, each generation comes with some really cool engineering details. However, there are a few years you might want to avoid for reasons that don’t have anything to do with the robust high-voltage hybrid system. See, a common issue with the third-generation Prius, model years 2010 to 2015, lies entirely within the combustion engine, and could deal a serious blow to the wallet of anyone looking for an inexpensive, economical daily driver.
These third-generation Priuses are known to suffer from premature head gasket failure, and that’s not good. The head gasket seals the cylinder head to the engine block. Not only does it prevent leaks in compression between cylinders, since an engine block has space for coolant around the cylinders, it prevents that coolant from escaping through the gap between the cylinder head and the block, which could have disastrous consequences if it leaks into a cylinder because coolant doesn’t compress or lubricate particularly well. Typical symptoms of head gasket failure can include a soaring temperature gauge, thick white smoke out of the exhaust, and rough running. It’s enough to ruin your day, let alone your wallet.
While the head gasket failure window on third-generation Prius models is wide, these cars are about nine years old at the newest, meaning most of them fall within that range of mileage. Some owners report gasket issues with well over 150,000 miles on the clock, but others report issues with as little as 70,000 miles travelled, such as the owner in this Reddit post below.
While some owners believed the issue to be isolated to pre-2014 models with early style piston rings, holes have been poked in that theory by recent reports of head gasket failures on 2014 and 2015 cars.
However, just because a Prius owner decides to bite the bullet and replace their blown head gasket, that doesn’t mean the issue won’t reappear, partly because the quality of such a repair depends highly on workmanship. This owner on PriusChat reports three blown head gaskets in 16,000 miles, at least two of which may have been due to shortcuts in the repair process such as not levelling out a warped cylinder head mating surface.
So, why are these head gaskets blowing so frequently? Well, there are two main schools of thought. Clogged exhaust gas recirculation systems can lead to excessive cylinder temperatures, and that can lead to detonation which can take its toll on the head gasket and internal surfaces. Another theory is that the hybrid system’s way of cycling the engine can lead to more cycles of thermal expansion and contraction, which can put added stress on key components.
Unfortunately, head gasket replacement on a third-generation Prius is a lengthy process calling for 18.8 hours of book labor. While a head gasket kit is fairly cheap, paying someone to do it can be prohibitively expensive. Keep in mind, cheaper examples are $5,000 cars, and most people shopping in that price bracket don’t have several grand sitting around to pump into engine repair.
Oh, and it’s not just third-generation Priuses that can suffer from head gasket failures. Other hybrids with the 2ZR-FXE engine, such as the Lexus CT200h and Toyota Prius v are also susceptible to failure. In fact, Speed Academy has an excellent video from when their CT200h suffered multiple head gasket failures.
It’s worth noting that not every third-generation Prius will suffer from head gasket failure. It’s hard to ballpark a failure rate, and many people still have great experiences with these cars. However, if you don’t want to or aren’t in a position to gamble with a problem prevalent enough to be thoroughly documented, there is a way of avoiding this head gasket issue altogether if you’re looking for an inexpensive, practical hybrid daily driver on a budget — go a few years older and pick up a second-generation Prius. The model sold between model years 2004 and 2009 is a great car, one that’s durable, reliable, spacious, and economical. In short, the one that made the Prius a juggernaut of a daily driver.
(Photo credits: Toyota, Reddit, PriusChat)
Support our mission of championing car culture by becoming an Official Autopian Member.
-
The Popular BMW B58 Inline-Six Engine Has One Big Achilles Heel
-
Here’s Why Busted Plastic Grille Flaps On A Newer Car Can Cause A Check Engine Light
-
If You Want To Buy A Cheap Jaguar, Here’s An Engine You Should Probably Avoid
-
Honda Pilots Only Just Stopped Featuring This Ancient Engine Technology That Most Cars Abandoned Over 50 Years Ago
-
The Nissan Variable Compression Ratio Engine Everyone Got Excited About Was Maybe Too Good To Be True
Got a hot tip? Send it to us here. Or check out the stories on our homepage.
The wildest thing I’ve noted about this issue is that it seems like the tolerance for it among owners is much higher than some other cars with major Achilles heels (owners on average seem more likely to pay for repairs and still be happy with the car overall I mean). I suspect this is due to to Toyotas overall reputation for reliability (I may have to fix this but nothing else will break expectations) as well as how much people seem to like their priui (proper plural of Prius???).
For people who like them, they’re really great cars.
High mileage 2nd generation Prius had a oil consumption problem that would sneak up on owners. One had to pay close attention to the oil level lest if got low which resulted in overheating. I wonder if Gen 3 had a similar issue that lead to the head gasket issue. Mine overheated due to my negligence at around 250k miles.
Even then, the oil consumption issue on Gen 2’s can usually be fixed. 98% of the time a piston soak takes care of it, or running an engine flush before an oil change. The drain holes on the oil control rings get clogged with carbon over time (affects some other Toyota 4-cylinders from the 90s-00s, and Saturns especially).
The Gen 2 I sold to my brother burned ~1qt/1000mi until I did a piston soak, dropped to ~1qt/4000mi. Ran some seafoam in the oil for a couple hundred miles, consumption dropped to ~0.5qt/5000mi. Recently switched to Valvoline Restore & Protect which should improve it even further or at least keep it the same.
Don’t know what I was expecting, but it sure wasn’t a head gasket job that just takes longer to take out more stuff.
That honestly doesn’t even sound like a bad thing. Just a somewhat stupid thing.
Why is changing a head gasket on a single bank of four cylinders so expensive? Is it because of the difficulty in accessing it due to the hybrid system?
It’s not really hybrid components that are in the way, but you have to remove the wiper assembly and windshield cowling thing, plus a bunch of the air ducting and the EGR system. The head is really buried in there. The cost is almost all labor
There are some YouTube videos out there. There are just a lot of parts to remove, not necessarily specific to the hybrid system. In fact, I think the hybrid stuff on the right side of the engine bay picture above, didn’t get touched.
For a company with such an impeccable reputation for reliability, Toyota really seems to have hit-and-miss luck with figuring out head gaskets.
Let’s see:
5M-GE
7M-GTE
3VZ-E
5VZ-FE
2AZ-FE
2GR-FKS
And here we have the 2ZR-FXE.
Did I miss any others?
Did 5VZ-FEs have head gasket issues? I had a Tacoma with one and it was rock solid from new to when I got rid of it with 211,000-ish miles on it and I don’t seem to remember seeing anyone complain about head gasket issues on the forums back then either.
I think it was more of a specific MY issue (’96-97?) and an intermittent, luck of the draw situation otherwise, but still a known thing.
That could explain it, mine was an 01. My dad bought it new and was never exactly gentile with it. By the time it was mine, mileage was somewhere in the 170,000 zone and I was a senior in high school. High school and early college me beat on that truck regularly and nothing would ever hurt it. I’m talking countless burnouts, limiter bashes, cold start redline blasts. It just shrugged it all off and kept on going.
There’s a reason you can find 2010 Prii for sale cheaper than a 2009. When I was shopping I was immediately skeptical when I saw that, and quickly found out about the head gasket issue.
The gen 2 is hardly perfect, they basically all burn oil as they get older, but they’ll burn oil as long as you’re willing to keep topping them off. Much cheaper than a head gasket job.
The oil consumption issue is usually just clogged drain holes on the oil control rings. A piston soak and/or a good engine flush usually resolves the problem and makes the oil burning negligible.
2nd Gen Prius is best prius. They are used as taxis everywhere and are largely free from problems. 3rd gen is not as reliable for a lot of reasons.
Our 2010 Prius started having head gasket issues at 180,000 miles. The options were to drive it till it dies or drop a new engine in. We elected to set our 14-year-old loose on it armed with YouTube, an empty summer, and his grandfather’s shop full of tools. Probably $800-$1000 later it runs like a champ, most of the expense was in getting the head machined down.
Note that we cleaned the EGR system beforehand, but it did not seem particularly clogged. I’m not convinced that caused the head gasket to fail. We added an oil catch can just in case.
The best value was not in keeping this old car on the road, but in inspiring a love of wrenching in my son. He is obsessed with fixing everything he can get his hands on now. And guess which car he gets when he turns 16 this fall?
We also have a 2014 v, which gulp. It’s only at 115,000 miles, and no issues so far, but it seems like just a matter of time. We added a catch can and cleaned out the EGR, but it feels like delaying the inevitable.
The thing that keeps me up at night is that I’ve got a 2016 Prius v. It lagged behind the main Prius, so was still a third gen model, but everyone lists the problematic years as “2010-2015” and nobody on the Internet seems to know whether Toyota actually fixed it for third gen 2016 models. I mean, I realize it’s a 99% chance that they’re just going by the years the main gen 3 Prius was manufactured, but… I can dream.
Knock on wood, but my 2013 has required nothing but regular maintenance over 160k miles. I’ll take that on any car I buy new.
Most of my miles were highway, although I commute less these days, so maybe I’ll avoid the HG issue for a bit. Maybe I’ll get wild and try and replace the EGR myself.
Also trying to find a good indie mechanic who might actually want to do a JDM engine swap if the time comes.
It is also worth noting that in some areas there are “Prius shops” that can bang out a Prius head gasket fairly inexpensively. I’ve seen as low as $2-3k on r/Prius. Unfortunately despite my area crawling with Toyota hybrids there don’t appear to be any shops that cater to them.
Or go any Prius C. Rock solid, but not as big nor comfortable as the regular Prius.
I manage a government fleet of about 200 vehicles, and we inherited two 2015 Prius V’s from another department. They both were given to employes who travel long distances on the freeway, every day, and both had HG failures between 250K and 275K miles. Both vehicles were impeccably maintained – we even proactively cleaned the problematic EGR passages, changed oil at 5K(full synthetic) and used Toyota coolant changed at prescribed intervals.
I can’t complain about the miles before failure – 275K is nothing to sneeze at – but considering the rest of the car, including the hybrid system, was completely trouble-free, it does seem like the HG are a definite weak spot.
So I have two Priuses and yes the Gen 2 is the most reliable. The head gasket issue seems to be directly related to long oil change intervals. Doing oil changes every 5000 miles helps mitigate this issue. The other problem with this generation is the brake accumulator. Luckily there was an extended warranty for that to 10 years/150,000 miles but its a very annoying problem. I will say that the cost savings in gas and general low maintenance makes it worth it.
I would love to know how regular oil changes prevent head gasket failure. That’s generally caused by issues with the cooling system, not oil.
There’s a great video describing the issue here, go to 25:50 https://www.youtube.com/watch?v=DxVdwwPp8kI&t=3s
Ah, I’m not entirely sure he’s saying the clogged piston rings cause head gasket failure or if he’s just saying that’s another problem that can cause expensive engine repair/replacements. Even if it gets bad enough to cause scoring on the cylinder walls I don’t see that affecting the head gasket.
Interesting that this is the same time frame car as some with the 3.5 V6 that is apparently prone to blowing head gaskets. I have read one person who posited that this was a result of their switch to the pink
long-life coolant as opposed to their traditional red. Probably BS, but it makes me wonder.
The gen 2 uses the pink LLC and it doesn’t have these problems. I’m dubious of this explanation.
Ick, stop reminding me.
-2012 Prius v owner
(Side note: bonus points for correctly using lowercase v. Still can’t believe they did that but it must be observed)
…in all seriousness, I feel so conflicted about this stuff. For one thing, I question whether it’s a case where, say, only a small percentage of these vehicles suffer this issue, but of course everyone who experiences it complains about it (rightfully!).
I’ve also heard people say it seems to be more for ones with city miles than highway miles.
A Toyota dealership technician relative said there’s not much to do, except that given the age, do the oil changes at 5,000 miles (rather than the 10,000 stated by the manual).
I did get the EGR preventatively cleaned out at 140,000 miles, although the jury’s still out on whether that actually helps avoid/postpone issues.
In the meantime, I get to worry about other reported potential issues like the brake accumulator, engine water pump, and of course, hybrid battery.
But, so long as none of those 4 problems strike simultaneously, I’m keeping this damn thing. I’ve been putting fun mods in it to make it my own.
Toyota is still the answer to the question “What car would you send your daughter out into the world in?”.
My daughter wants to go out into the world in a Wrangler. However neither of our current cars are Wranglers, so she’ll have to settle for a Mazda3 or an Accord.
Having worked as line tech at a Jeep/Eagle dealer I feel that Jeep is never the answer. It’s also interesting that the majority of new Ram/Jeep vehicle buyers are of the “sub-prime” loan category.
Volvo? Considering Toyota’s pretty bad about crash tests, my parents figured it’s worth the higher maintenance costs for us to be able to survive an accident.
Counterpoint: There are deals here. Good buddy of mine bought one of these with the gasket already blown and slapped a salvage engine in it. It’s treated him well.
Helps that he’s a mechanic, but anyone with some tools and time and a garage can do this if they have another car to drive while they do it.
Yeah, I’ve heard people say you can get cheap-ish low-mile JDM replacement engines. That’s still my plan if my Prius v suffers that. 153,000 miles and it’s fine so far. I had the EGR preventatively cleaned out at 140,000.
I think there might have been an article on this site about it, but cheap JDM engines are a thing. Something to do with tax structures making it expensive to keep older cars on the road in Japan, so TONS of good runners get parted out.
They also have very strict inspection requirements that fail older cars for basically non-issues.
It really is a wonder that the Japanese carmakers put as much effort into hardcore, long-after-the-warranty reliability as they do. The inspection situation in Germany is like that and look at where BMW & Merc ended up.
I’ve wondered about that and my guess is that it started as a way to win over larger export markets, particularly the US. To start out, they didn’t have power or size, but they had cheapness, durability, and serviceability that most European competitors were lacking, plus mileage the domestics couldn’t come near when the fuel crisis hit (a bit of luck there), pushing many people to try them out. Then, with the favorable yen:USD exchange rates, they smartly reinvested their profits into making even more durable (cast iron block with a forged bottom end in a 2.2 making all of 130 hp? Sure why not!*) and advanced tech, and improving rust protection (some more than others). Companies like Toyota skate a bit on that reputation today (like the Euros did/do on ancient race wins and much more interesting past cars). As for why they’re so strict at home, I have to guess it’s largely a way to subsidize the domestic industry by forcing more sales, though perhaps it’s a bit cultural, as well, IDK.
*Part of that might also have been driven by them looking to elevate their international image through motorsport and homologation rules meant overbuilt engines ended up in much detuned street cars. I’m an old Subaru guy, though this isn’t exclusive to them at all, but take the mk1 Legacy as an example, the model the Group A rally car was built from prior to the shorter wheelbase Impreza, back when homologation requirements were far more production oriented than later WRC. The renown EJ20G or EJ22T (unofficial designation for the closed block engine from the US model Legacy turbo) had bottom ends built for homologation reportedly good for 400hp+, but even the standard open deck engine had forged crank and rods, large journals, and strong journal overlap. In 1989, it had MPFI and electronic ignition (waste spark) with learning software and Subaru was not at the forefront of tech.
Just so happens I was recently watching a youtube video essay about the origins of the Japanese motorcycle industry, which truly did steamroll the world, scorched-earth style. Apparently racing culture was really big during the early days, when there were way more companies duking it out. It stuck.
Part of all that was an economic recession in Japan that forced export activity to maintain industrial output that would support the economy of an island nation of limited resources.
I’m sure a lot of it is cultural. Most tech products that are Japanese seem to last. My grandfather started buying only Japanese products for as many things as he could after getting fed up with American brands, and he still has a Brother printer and Panasonic vacuum from the ’90s (and their 2002 Camry V6). I’ve since bought a Brother printer and Panasonic vacuum and while the newer ones aren’t as nice, they’ve remained working for much longer than the HP printer and Shark vacuum they replaced.
I have a Sony alarm clock from the mid ’80s that I still use. Imagine getting smacked every morning for the past 40 years and still working.
2nd gen Prius has thus far proven itself to be the most reliable/longest-lasting Prius. I would never get a 3rd/4th gen. We don’t yet know enough about the current gen.
What’s up with 4th gen? I heard they were at least better than 3rd…
Well you have to look at the 4th Gen every day before getting in it.
….I never get this criticism. If I cared about looks more than MPG I wouldn’t be looking at a Prius in the first place. (And ironically, the newest generation reverses this to focus on looks at the cost of interior space.)
It’s not just caring more about looks than MPG, the 4th gen prius is quite possibly the worst looking modern car ever.
Are you talking before or after the facelift?
I just don’t see it. Looks fine to me.
Mostly before, but after isn’t that great either. Looks like a deep-sea creature.
I dunno, to me the gen4 feels like a very culturally Japanese product like we haven’t seen since the first JDM cars came over. I mean, the gen4 Prius was crazy popular in Japan with plenty of bodykits and even the Toyota GR styling package. They love the over-the-top almost Dekotora styling as seen too on other JDM offerings like the Alphard or Voxy. I can get behind it as an interesting example of a car that they didn’t really tailor for U.S. tastes despite selling it extensively here.
Yeah I didn’t buy a Prius for good looks. It is a transportation appliance with room for cargo, and generally does it better than anything.
Legendary Toyota reliability*
*1937-1995-ish.
While I recognize my own bias for another marque, I will still say that Toyota’s legendary reliability has outlived its actual truth.
How dare you speak such foulness in the Toyota circlejerk group chat.
Honorable mention also goes to the new TTV6 in the Tundra, and my buddy’s brand new Taco just spit out all its oil on the highway and seized the block with 600 mi on it. No motors available till “sometime in August”.
I have a feeling the 2020ish-2023 Tacos and Runners are going to be the “one to get” once people realize these new engines simply can’t compete with their outdated, inefficient predecessors in terms of longevity and simplicity of service. 465 ft/lbs does sound nice, but not at the price of high stress and complexity.
My sincere hope is that the Nissan Frontier with an NA V6 will be ‘the one to get’ over these new Tacos. The thing is dead simple and actually capable. The aftermarket for it is fine, if not good. There are also no crap manufacturers of aftermarket parts like you get when there is a dollar to be made off of burnt sienna lens moldings for your Wrangler (the royal “you”, not “you you”)
What other reason is there to tolerate chintzy, hard plastics, uncomfortable seats, and questionable styling if not for legendary reliability?
What does styling have anything to do with practicality and reliability?
Some will disagree with you on the seats. My Prius v seats are just fine. Never any pain after sitting in them, even for long periods. They work.
I don’t think I’ve sat in a Toyota made after 1995 with comfortable seats. And the problem with the styling is you have to look at it every time you get in and out of it.
It really only applies to the mass market cars they build and stake their reputation on. The Corolla and Camry used ancient, extremely well-vetted components forever because Toyota could be confident in how they would age. If you do your homework you can get similar results even from “unreliable” OEMs. Just buy something that hasn’t been changed in a long time. You’re just not going to get the best specs or performance or fuel economy or tech gimmicks.
Yep. Even the rather anti-US carmaker Consumer Reports rated the Chrysler 300 higher in reliability in its final years than the Toyota Avalon since it had been in production long enough that the reported issues started to diminish.
I have a buddy of mine that is 50+years old and has bought only two cars, a Cavalier and a Cavalier. Those things will run like crap longer than most cars run.
Or, to say it differently, I agree with you.