When Honda first released its current two-liter four-cylinder hybrid powertrain, it felt like a huge step forward. With primarily electric drive, it was smooth, powerful, and efficient right out of the gate. On the road, it really seemed like a have-your-cake-and-eat-it-too situation, plus it effectively replaced the much-maligned 1.5-liter turbocharged four-cylinder engine in high-trim Civics and CR-Vs. You know, the one known for diluting its own oil with excessive fuel and occasionally suffering from head gasket failure. While the hybrid powertrain did at least solve the former problem, now that it’s been on sale for a few years, head gasket issues have started to surface. Uh-oh.
As you’d probably expect, a head gasket is important for several reasons. It’s the seal between the cylinder head and the engine block, an often multi-layer steel affair snaking around various holes to keep each cylinder contained, each coolant channel water-tight, and each oil passage funnelling vital lubricant to-and-from the top end components. It has to hold up to each ignition event, well over 100 PSI in compression per cylinder, and the composition of the coolant. This gasket plays a big role, which means some not-so-funny things can happen if it fails to seal things properly.
Depending on where a head gasket fails, you could end up with a range of different problems. If the failure’s between a water jacket and an oil passage, you could end up with oil in your coolant or worse, coolant in your oil if it blows out between a cylinder and a water jacket. While the former’s not fun, the latter’s a real problem because coolant isn’t a particularly great lubricant. On the other hand, if it goes out between two cylinders, you could be in for misfires and poor running at the minimum. A head gasket failure between an oil passage and a cylinder can cause all that and excessive blow-by, while a head gasket failure between a coolant channel and a cylinder can lead to smoking and overheating. Just about the only benign sort of head gasket leak is a small weep from an oil passage to the outer edge of the gasket. This usually isn’t catastrophic, but it’s expensive to fix as the labor required can be rather intensive.
Right, quick primer on pretty much all the ways a head gasket can fail, onto Honda’s current four-cylinder hybrid powertrain. It uses a two-liter naturally aspirated engine based on the R-series family of engines found in models like the Acura ILX and 2012 Honda Civic, which means many of its fundamentals have been around for a while. Dubbed the “LF,” this family of engines can be found in the current Accord Hybrid, CR-V Hybrid, and Civic Hybrid, all of which sell in huge volumes. Matt Hardigree even has a CR-V Hybrid. Sorry if this causes any anxiety, Matt.
One poster on the CR-V Owners Club forum detailed how their 2023 CR-V Sport Hybrid suffered from a head gasket failure approximately 6,000 miles beyond the end of the factory warranty. After experiencing limp mode and a flurry of warning lights, this forum member had their CR-V towed to the dealership, where the technicians reportedly cleared the codes, cleaned the spark plugs, and sent the hybrid crossover on its way. Unsurprisingly, that wasn’t the end of the story.
The next day the diagnoses was a blown head gasket and possible bad cylinders. They wanted me to authorize the head teardown of 19hrs. A cost of $4000. Which I declined. I told then I’m going to call Honda of America. I’m waiting for a response. My question is: Am I the only person with a 2023 CRV hybrid, 17 months old with 66k miles with a blown head gasket?
As it turns out, the answer is no. This person is not the only Honda owner to experience head gasket failure on an LF-series engine. Not by a long shot.
Another CR-V Owners Club poster recounted experiencing two head gasket failures on their hybrid 2023 CR-V in 130,000 miles. While that’s some serious mileage for a three-model-year-old car, the poster’s outrage of “Now 2 replacements in 130k miles!? This isn’t right at all” is perfectly justified. A head gasket should be a lifetime part. Having it go out well before the 100,000-mile mark is a sign something’s probably wrong.
Over on Reddit, tales of head gasket woes continue even in a different chassis. This owner of a 2022 Honda Accord Hybrid reports similar symptoms to those seen by other owners of the same powertrain. At “about 94k miles,” an error message pertaining to the engine reportedly appeared on the dashboard. Given the mileage on the vehicle, you can probably guess what came next:
I took it to the dealership, and after running a diagnostic, they confirmed it’s a head gasket issue. The repair estimate was roughly four and a half grand, which really caught me off guard.
I mentioned to the service advisor that the cost felt a bit too much, and he said he’d check Honda’s system to see if there’s “anything they can do.” I didn’t specifically mention goodwill assistance, but that might be what he meant.
Fortunately, it does seem like Honda has some sort of goodwill policy regarding head gasket issues on two-liter hybrid models. In addition to the second CR-V owner above, this 2023 Accord Hybrid owner posted in the Accord subreddit detailing head gasket failure at 61,000 miles, along with what happened next.
First, let me explain how Honda handled my situation. I received an estimate to replace the head gasket of my internal combustion engine (part of the hybrid system) for $5,500 + tax. Hard pill to swallow. The dealership did not mention anything about a potential goodwill claim and it wasn’t until I searched online that I heard about it. After me talking to Honda corporate and the dealership service department, the service department put a claim through on my behalf. The good news is that Honda corporate covered a portion of it, my local dealership covered a portion, and my portion was only $1,500. So, we split three ways. Still more than I should pay to repair a 2 year old car, but better than paying full cost.
With multiple reports of “goodwill” compensation after the factory powertrain warranty ended, it’s likely that Honda’s aware of a failure pattern. Some technicians certainly are, as a post on the driveaccord.net forum details. “Happening to 2.0 hybrids. Working on one currently.”
Well, that’s a very clear blow between cylinders one and two. You can see where the dark head gasket material is missing clear as day thanks to the bright silver aluminum block peeking out through the gap.
In addition to forum posts, it doesn’t take much searching to find formal National Highway Traffic Safety Administration complaints over premature head gasket failure. Here’s one of a couple for the 2024 CR-V Hybrid filed in July. As the complaint states:
At 112,000 miles, the engine in my 2024 Honda CR-V Sport Hybrid (2.0L Atkinson-cycle engine) suffered a catastrophic head gasket failure, causing severe coolant intrusion into the cylinders. All scheduled maintenance intervals in the owner’s manual were followed and documented. The dealer and corporate (Case #16444920) have refused assistance. This is a widely documented mechanical defect where constant thermal cycling (the gas engine repeatedly turning on and off during hybrid operation) stretches the factory head bolts and destroys the gasket seal. This defect can lead to unexpected, total engine failure while driving at highway speeds, posing a severe safety risk to the occupants.
So what’s actually going wrong here? After all, head gaskets don’t normally just fail on most cars during normal engine operation. One theory right now has to do with thermal cycling. The head gasket provides a seal between the cylinder head and the engine block, but the actual clamping force is provided by long torque-to-yield bolts with different material composition than the aluminum engine block and cylinder head. As an engine heats up and cools down, those bolts thermally expand and contract at different rates than the block and head, and series-parallel hybrid cars are famous for lots of thermal cycling, what with the engine shutting down when electric power alone proves sufficient for forward drive.
Combine that with the high cylinder pressures that result from a nominal static compression ratio of 13.9:1, and hybrid vehicles tend to put a lot of stress on their head bolts. If clamping force falls out of spec, the head can start to lift, leading to head gasket failure. This is already a leading theory as to why third-generation Toyota Priuses suffer from known head gasket failures, and with similar engine cycling, it could be a contributing factor to reports of head gasket failure on Honda’s modern hybrid models. Of course, we won’t know for sure without a formal engineering report. I’ve reached out to Honda regarding reports of head gasket failure on two-liter hybrid models, and will update this as soon as I hear back.
On the plus side, Honda does seem to be aware of this issue in at least one market. A “product update campaign” was issued by Honda Canada on July 16 covering 2025 to 2026 Civic Hybrid, 2023 to 2025 Accord Hybrid, and 2023 to 2026 CR-V Hybrid models. The code on the bulletin is Q79, and it’s titled “Head Gasket May Develop an Internal Coolant Leak.” The initial move seems to be a software update covering cooling system calibration, and while this campaign’s only in Canada right now, it wouldn’t be surprising to see something similar make its way stateside soon.
If you happen to own a late-model CR-V Hybrid, Accord Hybrid, or Civic Hybrid, don’t panic yet. There appears to be a pattern of possible partial coverage if a head gasket failure happens outside of the warranty period, and Honda does appear to be aware of this issue. It’s also worth noting that Honda sells huge quantities of hybrid cars in America, so a bunch of complaints doesn’t mean that every single example will be affected. However, it is worth noting that expanding availability of the two-liter hybrid powertrain hasn’t turned out to be a silver bullet for Honda’s 1.5T problems. This is a developing story, so expect more news as further developments surface.
Top graphic image: Honda
Well, shit.
Should have used ARP head studs.
My former Ford C-Max Hybrid had 275k on the engine when it was taken out by a car that pulled out in front of me. Only engine issue was a coil pack that needed to be replaced. Used engines for them cost like $300 because they never fail.
“Thermal cycles” seem to be the magic here…
These things can remain cold for a long time, with the computers trying to keep the engine off as much as possible.
There is no logic in a hybrid, to my knowledge, where the ECU would put a requirement to keep the engine warm.
On our Sportage Hybrid, there is a temp gauge that is buried in the menus, and it is weird (or concerning). The temp goes from low to mid all the time. It’s like it either measures some temp variations within the working temperature, OR the cooling system is set to dynamically let the engine go to temp very fast, by controlling the coolant output.
The part in the article about “Recalibrating the ECU” to solve a cooling problem also goes in that direction.
At least on the Sportage, putting it in Snow mode keeps the engine running all the time. Maybe I should put it in my daily routine, for the first fifteen minutes of driving or whatever.
Hybrids have a lot of logic to keep the engine warm. They need to keep it warm (especially the cat) for emissions reasons. If the engine gets too cold, they will re-light the engine. I’m not sure how this is handled in PHEV, though.
*Most* PHEVs will keep the engine off when there’s enough battery juice unless its below freezing.
Simultaneously, they keep tract of engine off time and will run the engine regardless of battery state if the engine hasn’t seen enough runtime in a predetermined amount of time.
I’m extremely dubious of this thermal cycling theory. Regular hybrids don’t shut their engines off that long in regular use. The only time I see significant temp changes in my Prius is in the dead of winter on long downhills (which, frankly, is also true of my non-hybrid vehicles). It’s not like shutting off the engine for 30 seconds while you wait at a stop light is letting it cool off that much. And these don’t have large enough batteries to drive long with the engine off.
Plus, the gen 2 Prius engines are basically bombproof. How is it that one of the first hybrid engines that was produced in massive quantities (many of which are still on the road 20+ years later) managed to avoid this supposedly hybrid-specific problem when newer ones can’t?
I’m betting (and we’ll never know because neither Toyota nor Honda will ever admit publicly what the problem was) that the answer is what it usually is: cost cutting. Someone, somewhere, decided that they could get by with one size smaller head bolts (or something like that) and save 5 cents per engine. And that 5 cent savings is costing their customers dearly.
Friend and fellow co-worker (driver) of mine has an older Prius and it recently had to have the head gasket changed. He also got the hood repainted under a customer satisfaction program.
How old though? A gen 3 from 2010 definitely qualifies as “older” at this point and those are the ones that are known to have head gasket issues. Most gen 2 (2004-2009) Prii die because their engines consume oil at higher mileages and the fourth owner forgets to check it.
“If you happen to own a late-model CR-V Hybrid, Accord Hybrid, or Civic Hybrid, don’t panic yet. There appears to be a pattern of possible partial coverage if a head gasket failure happens outside of the warranty period, and Honda does appear to be aware of this issue.”
Ah ok then.
This issue in the very least proves the point that I try to state that past performance does not guarantee future results just like the stock market. So far, the Nissan-supplied PR25DD engines in both of our Outlanders have been trouble free and the engine in the ‘26 models with the mild-hybrid 1.5T has been around long enough to prove its reliability and workmanship as well. Just because the last 20 years of production has brought a stellar reputation doesn’t mean it it here to stay.
No one seems to remember the “glass transmissions” in Odyssey and Accord models or the across the board AC compressors imploding on UK-built CRV of which there were MANY thousands…
Sometimes thinking outside of the box can give you REAL piece of mind…
Thanks to you, Mitsubishi.
Over time the failure rate will be determined. Provided Honda stands behind their engines with a written extension of warranty to 100,000 miles or beyond then this issue will not create Hyundai oil burning level of reputation harm.
I don’t get some of the more recent, very un-Honda and Toyota problems of late. Honda I think was first before Toyota with their hybrids back in the day and I still see a lot of those out there running about. I don’t trust the new Tacoma or Tundra from Toyotas as they too are having some problems.
$5500 for a head gasket repair seems really steep
It’s likely dealer pricing, if the customer doesn’t bounce, they either get paid or sell another car. Win-win.
They call them “Stealerships” for a reason
Just a gasket replacement would likely be under $200 or $300, just a guess from seeing things like this in service departments over the years. But, replacing the gasket, along with all of the parts of the engine damaged when the gasket failed, plus labor, is where it gets more expensive.
A head gasket? No way. 1 hour of labor is $200 bucks at the dealer now, and I’m guessing 10-15 hours of it.
Between this and the Forester, I think the Autopian should have an “Inverse Matt Hardigree” list of approved Midsizers
I have a 2024 CR/V Hybrid with 20,000 miles on it. Was debating on trading it for something bigger and this probably is going to push me in that direction now. Sounds like it’s a ticking time bomb that will fail at some point.
You barely drive it. Why would you even consider trading and taking the depreciation hit versus a probably <10% chance the head gasket will fail in your ownership
The bigger crime is the dealer who put down 19 hours for the head gasket replacement on the estimate. Ouch. Apparently Honda must take their customers for suckers.
You would need to see what’s involved. Like the time my brother and I changed the timing belt on his 98 Avalon. It took all weekend because all of this other shit had to come off first. When we were done I later found it was a 12 hour job at the dealer.
A lot of newer cars have to have dumb shit done to them like remove the whole engine, the transmission and so on just to get the part off. Not sure what’s involved with this one but could be something equally obnoxious.
It wouldn’t be the first time Canada gets a repair campaign the US doesn’t from Honda. Element rear subframes mounts rot to the point where the rear wheels collapse rearward into the Element and total it. Canada got a recall for an extra bracket the US cars across the border didn’t. On copart you’ll see clean looking Elements with the rear wheels shunted backwards from it.
A couple notes (from someone who may have been involved in that while working at Honda…) –
That campaign eventually expanded to the Element, Pilot, and Ridgeline both in the US and Canada.
Two reasons for the difference in Canada vs USA – #1, this was a corrosion problem, and Canada’s conditions were more severe. Eventually all the rust belt states were included as well. #2 – this was originally driven by a change in consumer protection laws in Canada. The US eventually caught up, but it is an example of strong consumer protections benefitting customers and why it’s important to have strong consumer protection laws.
Hmmm.
It’s almost like going Hybrid – with all it’s complexities and potential failure points – is not as smart a choice as going full EV.
If only surveys haven’t shown that between ICE, Hybrid and BEV, hybrids have the fewest problems for owners.
I suppose that if exploding engines as an issue are counted the same as a malfunctioning door handle…
Umm, why does it being hybrid have to do with headgaskets failing? In general, Hybrid cars are typically among the most reliable vehicles on the road, and are usually the most reliable car in a brand’s lineup.
As the article states, it may have something to do with the higher number of thermal cycles the engine experiences precisely because it’s a hybrid.
Normally I would think the ICE part of the drivetrain would be pretty robust, because the electric motor deals with most (if not all) of the high load events so the ICE shouldn’t be overly stressed.
In this case, it sounds like a material science issue, where the different expansion rates between the block and the head bolts is resulting in the head bolts getting stretched over time, thus losing some of their clamping force on the gasket, and ultimately leading to blowouts.
With different material selections or larger head bolts, this might not be a problem, but I’m not a mechanical engineer so I couldn’t tell you for sure.
Another option might be routine tightening of the head bolts, but that may not be practical.
Our 2009 Fit just experienced an unrelated but similar issue. Apparently the 1.5 liter engine in them is known for having the spark plugs unscrew themselves and eventually get blasted out of the head, stripping out the threads as it goes. I fixed it with a helicoil insert, and while I was at it I decided to replace the other three spark plugs. It turned out one of them required no torque whatsoever to loosen – it was on the verge of joining it’s neighbor in violently separating itself from the vehicle.
I’ll be checking them annually from now on, even though they’re on the back of the engine and a pain to get to – not something a typical driver would under take, like say tightening head bolts, for example. 🙂
Hybrids have been around for the better part of 30 years. Some are really reliable, and some have problems like any other car. We had a 2002 Prius. Never had an issue past 250,000 miles.
Hmm.
A Tesla high-voltage battery replacement at an official service center typically costs between $12,000 and $22,000
And a new Honda engine for a hybrid from the dealer installed is somewhere in the 10-14K range.
So what?
One common denominator you see amongst almost all of these head-gasket blowing engines is that they’re all open deck designs. Honda 1.5, 2.0. The Ford Ecoboosts inline engines, the Chrysler 3.6, Subaru Boxers, and so on. Even with the Toyota 1GR V6 and 3UR V8 engines which are extremely reliable, about the only major failure they sometimes encounter is a late-life head gasket failure (usually 200k+).
That’s not to say all open deck engines blow gaskets, but it seems very difficult to keep them sealed.
Virtually all modern engines are open deck regardless of brand…
Wonder if regular check/tughtening of the bolts prevents the ussue. I remember somewhat similar thing happen on my turbo engine when the exhaust mainfold bolts stretched over time. It wasn’t as dangerous as no oil/coolant involved, but on a cold engine, the car farted more than me on a morning after a beer party.
The article notes that they’re torque-to-yield fasteners, which means you can’t really just tighten them up, A torque-to-yield fastener is deformed by the act of cinching it down correctly, so if it’s loose (either intentionally or unintentionally), the fastener needs to be replaced.
Its still loss of preload tho…..unless its a crappy gasket LOL. Id look at aftermarket bolts that arent TTY and check them periodically once out of warranty.
+1 for using stronger fasteners for more clamping load
Toyota and Honda have been getting high on their own supply. Building up a reputation takes decades but tearing that back down is more of a sudden, cliff-fall.
Having to pay ONE CENT to repair a headgasket on a 2 year old car is just bonkers to me. If it’s under 5 years old, the manufacturer better handle ALL of it, for the most part.
WTF Honda!? Are you trying to squander the reputation you spend decades building entirely?
That + the GM Prologue isn’t a good way to promote your EVs.
Didn’t Honda lose a bunch of $$ this past fiscal year, for the first time in decades?
They lost that money by writing down all of their in-house EV efforts.
I hear you, but how about instead we focus on next quarters profits and ignore everything else
I’d be very interested to see a regional distribution of these complaints. Hondas are happiest around the 35th parallel.
I wouldn’t risk either of these engines outside of warranty or expect any kind of goodwill. 5 grand to get your sub-100K mile Honda back on the road because they committed the engineering oversight you’d expect from a third-tier automaker on a critical powertrain component is going to sour a lot of people.
This is the kind of failure severity and cost that gave the Jatco CVT in Nissans such an enviable reputation.
I’ll be watching this. My mother in law traded in a 1.5t Accord for a CRV Hybrid. I thought she dodged a bullet getting out of the Accord before this could happen, but maybe not.
Yesterday a new recall service bulletin dropped in the US market for the same updates on the 2025 to 2026 Civic Hybrid, 2023 to 2025 Accord Hybrid, and 2023 to 2026 CR-V Hybrid models. Our verbiage on the “background information” on the why we are doing it was a bit different. Still no word on what will come of the class actions for the 2.0 hybrid and 1.5t head-gasket failures on the older cars. I wouldn’t be surprised to see at least a warranty extension on the older hybrid vehicles for replacement + software update.
Man I feel like Hondas’ always had head gasket issues. Nobody was modding corollas in the 90s because the engines just kept running. Hondas popped at 80k to 100k and that kept a steady supply for young mechanics to buy. Or owners got sucked in to the “while you’re in there anyway” mods fallacy. D series were open deck was the refrain I remember in sport compact car(rip)
That being said my 2024 k20z7 equipped civic with 22k miles is burning a quart of oil every 1000miles which Honda claims is within service limit. So even the reliable Honda engine is a flawed in my opinion.
I frequently saw blue smoke from the famously “bulletproof” ’90s Hondas back in the ’90s. Only cars I ever saw blowing blue smoke as much were K cars (which matched the light blue it seemed 60% of them were painted). Meanwhile, my “head gasket eating” Subaru Legacy (2.2, not the 2.5) took an absolute beating for 250k miles, hardly used any oil, and delivered actual torque before burning an exhaust valve. Tore it down and the top end looked almost new, cylinder crosshatching all intact, and I could feel no wear on the bottom end bearings. Literally a $12 exhaust valve was the only issue—not even any scoring in the cylinder from melted bits.
True.The body shop I worked at did a lot of local Honda dealer work back in the 90’s.The dealer drivers would always have to check the oil before they drove them back for customer delivery because they were notorious for eating oil.I believe that was the 5th and 6th gen Civics.
Let me guess, fixing rust at the back of the rear wheelarches where they meet the back bumper cover?
The D16 in my 90 Si blows mad smoke, so much that it’s impossible to keep the ass end clean.
Lucky! An ex had a parade of constantly-busted Subarus, and my brother bought a new 2010 Outback that was falling apart the minute he bought it.
I’ve got the same blue-over-gold lust as any breathing human, but I’ll be damned if I ever so much as recommend a Subaru.
Lucky nothing. The EJ22s were great engines. It’s the EJ25s that sucked. The engine family was designed in the mid ’80s and, IMO, with 2.2 being the design maximum (US only, where we like torque) for cars weighing about 1k lbs more than what they were making at the time. Mid 90s, the Outback, fatter and heavier than anticipated when the EJ was developed, was a huge hit, but required a bigger engine, so they stretched it to 2.5 when the problems began (and added DOHC that made them harder to service). This wasn’t helped by greater limitations when increasing displacement in a boxer engine resulting in an even more oversquare engine, which is why they had issues with piston slap and head gaskets. The earlier EJ22s were SOHC with simple plug changes right on top, non-interference engines (later became interference, I believe) with forged crank and rods. They ran MPFI, distributorless ignition (something Honda didn’t have), and effective learning software. Even the fasteners used only required a minimal number of tool sizes. The turbo added stronger pistons, oil squirters, and a closed deck block. People beat the absolute hell out of them, too, and they were sought after well into the STI era for their durability. Only issue was the EJ22T heads didn’t flow well at all as they were designed for use with a small turbo and no intercooler to reduce lag (pretty much eliminated). Foreign markets used a 2.0 version with much better heads.