Shops quote $2,710–$3,278 for this one, and the quote usually isn't the ripoff, the job really is that big. Here's what's actually failing, what the correct repair involves, and the honest part: this is not a job I do in a driveway.
The 2014–2020 MDX's J35Y5 runs VCM cylinder deactivation, and the cylinders it shuts down most, the 4-5-6 bank, live a strange thermal life: combustion off, then on, then off, cycling through temperature swings the front bank never sees. Over years, that uneven heat distorts the sealing environment, and the head gasket on that bank begins to weep. It rarely fails dramatically; it leaks coolant slowly into a cylinder or toward the exhaust port, which is why the symptoms are subtle at first.
The signature is white exhaust vapor on warm-up, coolant that seeped into a cylinder overnight, steaming off on the first drive, plus a sweet coolant smell, a reservoir that bubbles after a run, and a coolant level that drops week after week with no puddle on the driveway and no visible leak anywhere. In traffic on a hot day, the temperature gauge starts creeping, because the system is slowly losing both coolant and its ability to hold pressure.
The repair is bank-specific: the affected cylinder head comes off, the deck and head get checked for flatness, and a new gasket goes on with new head bolts. The smart bundle is the cooling refresh while the system is already drained and apart, thermostat, aging hoses, and a full flush, because a marginal cooling system is part of what cooked the gasket, and reusing it puts the same stress on the new one.
If your Acura is doing any of these, this is the likely cause:
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Head Gasket Replacement (Single Bank) with Cooling System Refresh is on my published list of jobs I turn down. It needs a hoist, a press or a machine shop, and I work out of driveways with hand tools. That list is public on my trust page. I'd rather lose the job than learn it on your engine, and you should be suspicious of anyone who says yes to this over the phone.
So here's what I can genuinely do for you, holding a $2,710–$3,278 quote. Both are real, both are flat-priced, and both are worth more than a bad yes.
Before you spend $2,710–$3,278, have someone independent confirm that's actually what's wrong. This is a diagnosis, not the repair, no hoist, no lift, nothing comes apart. I scan it, test it, look at it with you, and tell you straight whether their diagnosis holds up. If it does, I say so and you go pay them with confidence.
Book the second opinion →At $2,710–$3,278 on a car that might be worth not much more, plenty of people replace instead of repair, that's a completely reasonable call. If that's where you're heading, get the next car measured before you hand over money: 150 published points, at the seller's location, written report the same day.
Book a pre-purchase inspection →Tell me what you've been quoted and what the car is doing. $100–$250 flat, at your location, and you get a straight answer either way.
Rather just have the quote read? The free quote check tells you whether the number is in line, no visit needed.
Jobs on this car that ARE mine:
Not so you can do it yourself, so you can tell whether the shop quoting you understands the job:
That's the job. It's why this one belongs on a hoist instead of in a driveway, and it's why $2,710–$3,278 usually isn't a ripoff, it's a big repair honestly priced. What's worth checking is whether that's really what your car needs.
Get the diagnosis confirmed firstPlain version: Head Gasket Replacement (Single Bank) with Cooling System Refresh needs equipment a driveway doesn't have, a hoist to get under it properly, a press or a machine shop for the parts that come out, and a controlled space for an engine or gearbox that's in pieces for days. I work out of driveways with hand tools. That's not false modesty, it's the published limit of what I take on, and it's listed on my trust page alongside the warranty.
What that means for you: this page is here to tell you what's failing and what it should cost, so you walk into a shop knowing the job instead of nodding at a number. And if you want that number checked before you pay it, that part I can do, $100–$250 flat, at your location.
A weeping head gasket only travels one direction. Coolant in a cylinder washes the oil film off that bore and contaminates the engine oil; coolant loss plus traffic heat is how a weep becomes a warp, and a warped head turns a gasket job into machining or a replacement head. The truly expensive ending is an overheat event on the 401, aluminum heads tolerate exactly one bad overheat, sometimes zero. Caught at the white-smoke-and-slow-loss stage, this is a contained, predictable repair.
Sometimes, and that's a much cheaper day, so we test before we tear down. A pressure test, a look at the plugs on the rear bank, and a combustion-gas test on the coolant tell us definitively whether the gasket is breached. You only get the head gasket quote if the evidence says head gasket.
The failure pattern on these engines centres on the VCM-cycled rear bank, that's the one living through the temperature swings. The front bank doesn't share that stress and rarely follows. We inspect both banks' plugs and compression while we're in there, so you know the state of the whole engine, not just the repaired half.
No. Head Gasket Replacement (Single Bank) with Cooling System Refresh is on my published list of jobs I turn down, it needs a hoist, a press or a machine shop, and I work out of driveways with hand tools. I'd rather lose the job than learn it on your engine.
Two things, and both are real. A second-opinion diagnostic at your car, $100–$250 flat, at your location, so somebody independent confirms that's actually what's wrong before you commit to a $2,710–$3,278 repair. And if you're weighing replacing the car instead of fixing it, a pre-purchase inspection on the replacement, $149–$399 flat, at the seller's location.
Because the useful part isn't the wrench. It's knowing what's actually failing, what the correct repair involves, and that shops quote $2,710–$3,278 for it, so you walk in knowing the job instead of nodding at a number. If you want that number checked before you pay it, that part I can do.
Send it over for a free second opinion. I'll tell you straight what the job actually involves, and if their quote is fair, I'll tell you that too.
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I'm not the guy who does this repair. I'm the guy who tells you whether you actually need it, before you spend $2,710–$3,278. Second opinion at your car, $100–$250 flat, in Mississauga, Oakville, Milton, Brampton and Etobicoke.
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