Poll 2.5T Coolant Leak/Engine Replacement

Who is having coolant leak issues and have had their engines replaced?

  • Yes

    Votes: 46 39.0%
  • No

    Votes: 72 61.0%

  • Total voters
    118
So here is the update: they have filed with our extended warranty company (CarShield) for a head replacement and a new transmission (different problem). This is about $15K worth of work. We are waiting to hear back from the warranty company adjuster. We talked to them on the phone at least twice - between myself and the service advisor (Phil) - and the last I heard was that they have "elevated" the process to the adjuster supervisor on their end. The dealer filed this paperwork on the 17th and our car has been in the shop since the 8th (of Nov)! Waiting to hear on whether they will cover the repairs. The dealer decided NOT to pursue a remedy through Mazda, but if the warranty company rejects, that may be the next step. I cannot afford a $15K repair on this car at this time.
Another update: My warranty company will not cover the head replacement, since it is a "manufacturer defect" according to them...but they ARE covering a transmission replacement with a "used" transmission that they will warranty for 1 year or 12K miles. So, I don't think I mentioned that the transmission was jerking between 2nd and 3rd gear on both up and downshifts and this was one of the other reasons I took the CX-9 in (on November 8th...but who's counting?). They diagnosed it as bad. Anyway, back on the head: the dealer will now approach Mazda corporate with a request to cover the repair. Judging from the entries on this forum, this has been a mixed bag, with some getting a "good will" repair and others not getting it approved. If anyone can provide/post any official communications with mazda...i.e., a letter, e-mail, anything that says they covered their head or engine replacement (for a car out of warranty) this would really be helpful to me as I make my case. Perhaps it is a lost cause...I cannot afford the 7K that the dealer would charge to replace the head, nor do I think it would be worth it to pay that much to make that kind of repair...although it is cheaper than a "new" car, I suppose. This really sucks. I've had 3 Mazdas and would like to stay with the brand, but after this, I really don't think I will. Meanwhile we continue to use a loaner 2022 CX-9, who knows how much longer we'll need to have that?
 
I'm contemplating what I will do if this happens to either my CX-9 or Mazda6. Whether to do the repair or dump it as a trade. I'm likely leaning on the latter. I don't think I feel like going through the whole process, spending all that money, and not be confident with the repair.

Anyone have experience trading in a vehicle needing a new engine or transmission? Is it a simple value deduction of the repair cost or will the dealer take even more off the value than the repair because of the hassle?
 
I'm contemplating what I will do if this happens to either my CX-9 or Mazda6. Whether to do the repair or dump it as a trade. I'm likely leaning on the latter. I don't think I feel like going through the whole process, spending all that money, and not be confident with the repair.

Anyone have experience trading in a vehicle needing a new engine or transmission? Is it a simple value deduction of the repair cost or will the dealer take even more off the value than the repair because of the hassle?
I’m actually contemplating the same. This is my 5th Mazda but now looking into a different Japanese automaker. I believe this issue is a ticking bomb.
 
Another update: My warranty company will not cover the head replacement, since it is a "manufacturer defect" according to them...but they ARE covering a transmission replacement with a "used" transmission that they will warranty for 1 year or 12K miles.

WTH? That's the whole purpose of a warranty to cover defects and such. That's the whole damn definition of a warranty. You need to reread the paperwork you signed. Did they truly write the impossible warranty? Sounds like they left themselves an out for everything.

Next they'll be telling you the transmission not covered because they think it was driven too in much.

Did the dealership sell you this extended warranty? Is it one of those name brands warranty that advertises on tv?

You need to tell them that's fine, you'll just Facebook and Twitter that they're warranty is a sham(after you've read your contract though) and especially if they try to deny the tranny repair. Maybe wait and see what happens with the tranny repair before you explode on them. Your sort of in a tough spot because if you complain they could decide to not fix anything.

Also, if Mazda won't goodwill the repair, then see if a local mechanic, engine shop or machine shop can install a new engine, head or even a used salvage engine just to get it going for far less than the dealer prices.
 
Last edited:
WTH? That's the whole purpose of a warranty to cover defects and such. That's the whole damn definition of a warranty. You need to reread the paperwork you signed. Did they truly write the impossible warranty? Sounds like they left themselves an out for everything.
Next they'll be telling you the transmission not covered because they think it was driven too in much. Did the dealership sell you this extended warranty? Is it one of those name brands warranty that advertises on tv? You need to tell them that's fine, you'll just Facebook and Twitter that they're warranty is a sham(after you've read your contract though).
Gotta love these warranty companies. They have an out for everything. So if they don't cover failures due to defects, the only other thing would be covering wear and tear. Nope! We all know wear and tear isn't covered.
 
Like Jack said, defects in materials and workmanship is exactly what a warranty covers and usually the ONLY thing warranties cover. A failure due to something out of your control and catastrophic should absolutely without a doubt be covered or the company is a sham, and like I said if it's carshield then it is a given. If you don't get any results from Mazda then you will be forced to put that company on blast on every social media platform and group you can. I'd even contact the local news and ask if they would like a juicy story on a scam warranty company who advertises heavily with celebrities on tv refusing to pay for a legitimate claim you have. Make it known you will not go away. That's the only way these underhanded companies will take action and apologize.

If you don't want any hassle and not spend anything, then take it to CarMax etc and sell outright or trade in for another vehicle from them. Hoping Mazda helps you out though first.
 
Last edited:
Another update: My warranty company will not cover the head replacement, since it is a "manufacturer defect" according to them...but they ARE covering a transmission replacement with a "used" transmission that they will warranty for 1 year or 12K miles. So, I don't think I mentioned that the transmission was jerking between 2nd and 3rd gear on both up and downshifts and this was one of the other reasons I took the CX-9 in (on November 8th...but who's counting?). They diagnosed it as bad. Anyway, back on the head: the dealer will now approach Mazda corporate with a request to cover the repair. Judging from the entries on this forum, this has been a mixed bag, with some getting a "good will" repair and others not getting it approved. If anyone can provide/post any official communications with mazda...i.e., a letter, e-mail, anything that says they covered their head or engine replacement (for a car out of warranty) this would really be helpful to me as I make my case. Perhaps it is a lost cause...I cannot afford the 7K that the dealer would charge to replace the head, nor do I think it would be worth it to pay that much to make that kind of repair...although it is cheaper than a "new" car, I suppose. This really sucks. I've had 3 Mazdas and would like to stay with the brand, but after this, I really don't think I will. Meanwhile we continue to use a loaner 2022 CX-9, who knows how much longer we'll need to have that?
So, the saga continues. Mazda agreed to cover a portion of a "good will" repair, replacing the head on our CX-9, knocking the original dealer quoted repair cost of a whopping $6700 down to ~$2800. While that is still a lot of money to sink into a car from 2016 that has 78K miles on it, it is much less than getting another one...even a used one; but if you got a used CX-9, you are back in the same spot with the potential head issue (unless you buy a newer one that is not subject to the problem). Anyway, I have not accepted the offer yet. I do think that the turbo should be replaced along with this new head. Any mechanic worth his/her salt would replace a turbo that is almost 7 years old and has 78K miles on it if they were replacing the head. I am not sure if the dealer would do this, but I have asked them about it. I'll see what they say. Any thoughts from this community on whether the turbo should be replaced at the same time? A rebuilt one wouldn't be that expensive, and NOW is the time to do it.
 
So, the saga continues. Mazda agreed to cover a portion of a "good will" repair, replacing the head on our CX-9, knocking the original dealer quoted repair cost of a whopping $6700 down to ~$2800. While that is still a lot of money to sink into a car from 2016 that has 78K miles on it, it is much less than getting another one...even a used one; but if you got a used CX-9, you are back in the same spot with the potential head issue (unless you buy a newer one that is not subject to the problem). Anyway, I have not accepted the offer yet. I do think that the turbo should be replaced along with this new head. Any mechanic worth his/her salt would replace a turbo that is almost 7 years old and has 78K miles on it if they were replacing the head. I am not sure if the dealer would do this, but I have asked them about it. I'll see what they say. Any thoughts from this community on whether the turbo should be replaced at the same time? A rebuilt one wouldn't be that expensive, and NOW is the time to do it.
That's great news. You really should get your extended warranty to cover the other $2800. You shouldnt be out of pocket on this.

As far as the turbo, if you are willing to pay parts and labor, you could ask how much and ask them to include that, especially if you are keeping the car for another several years. Otherwise why bother?
 
So, the saga continues. Mazda agreed to cover a portion of a "good will" repair, replacing the head on our CX-9, knocking the original dealer quoted repair cost of a whopping $6700 down to ~$2800. While that is still a lot of money to sink into a car from 2016 that has 78K miles on it, it is much less than getting another one...even a used one; but if you got a used CX-9, you are back in the same spot with the potential head issue (unless you buy a newer one that is not subject to the problem). Anyway, I have not accepted the offer yet. I do think that the turbo should be replaced along with this new head. Any mechanic worth his/her salt would replace a turbo that is almost 7 years old and has 78K miles on it if they were replacing the head. I am not sure if the dealer would do this, but I have asked them about it. I'll see what they say. Any thoughts from this community on whether the turbo should be replaced at the same time? A rebuilt one wouldn't be that expensive, and NOW is the time to do it.
I just picked up my CX-9 2018. Got a new cylinder head on the warranty. The cost would have been 4000 $ accordingly to the service guy….. (16.5 hours + material)
 
So, the saga continues. Mazda agreed to cover a portion of a "good will" repair, replacing the head on our CX-9, knocking the original dealer quoted repair cost of a whopping $6700 down to ~$2800. While that is still a lot of money to sink into a car from 2016 that has 78K miles on it, it is much less than getting another one...even a used one; but if you got a used CX-9, you are back in the same spot with the potential head issue (unless you buy a newer one that is not subject to the problem). Anyway, I have not accepted the offer yet. I do think that the turbo should be replaced along with this new head. Any mechanic worth his/her salt would replace a turbo that is almost 7 years old and has 78K miles on it if they were replacing the head. I am not sure if the dealer would do this, but I have asked them about it. I'll see what they say. Any thoughts from this community on whether the turbo should be replaced at the same time? A rebuilt one wouldn't be that expensive, and NOW is the time to do it.

As far as the turbo goes, it is 2022, not 1982. Turbochargers routinely outlast the rest of the car these days as long as they are maintained. For instance, I have a 19 year old Subaru with the original turbo that routinely seeds redline, full boost, etc. Further, I do not recall a single post on this forum where a turbo went bad. You've been changing the oil on schedule, yes?

If you want a new turbo, honestly I'd ask Mazda if they'd conisder taking your current CX-9 in trade and throw in the $3900 goodwill towards a new car.
 
I'm new to this forum. This is very concerning. I wanted to keep the car long term, but now I'm having serious doubts. Getting this at 80,000 miles could be costly. I doubt Mazda would do a recall.

Is anyone thinking similar?

I'm having doubts. Got mine just over 3 yrs ago, 2019 leased. Love it. Figured I'd buy it out after the 5 yr term ends, since the buyout prob will still be a deal compared to the market then.

I'm super low km as well, car has hardly moved in covid. So buying out seemed a no brainer.

Now I guess I'm glad that (I think?) my 5 yr lease coincides with my powertrain warranty. I'll be forced into a decision before my coverage runs out.

For anyone reading this, I'm pretty green wrt engine stuff, so I've looked at some of the advice here for detection. Smells, inspect levels in the tank (I'll look later to make sure I can even locate this tank), watch for puddling. Watch for fluid in engine bay where it's not supposed to be. Check dipstick. Seems this is all done best with engine cold?

Anyone have other advice? I do unfortunately tend to have a heavy foot and I also tow.

This wasn't the news I wanted, regardless of how rare it is. And yay for me, I also have a 17 CRV so engines are now my achilles heel.
 
I'm having doubts. Got mine just over 3 yrs ago, 2019 leased. Love it. Figured I'd buy it out after the 5 yr term ends, since the buyout prob will still be a deal compared to the market then.

I'm super low km as well, car has hardly moved in covid. So buying out seemed a no brainer.

Now I guess I'm glad that (I think?) my 5 yr lease coincides with my powertrain warranty. I'll be forced into a decision before my coverage runs out.

For anyone reading this, I'm pretty green wrt engine stuff, so I've looked at some of the advice here for detection. Smells, inspect levels in the tank (I'll look later to make sure I can even locate this tank), watch for puddling. Watch for fluid in engine bay where it's not supposed to be. Check dipstick. Seems this is all done best with engine cold?

Anyone have other advice? I do unfortunately tend to have a heavy foot and I also tow.

This wasn't the news I wanted, regardless of how rare it is. And yay for me, I also have a 17 CRV so engines are now my achilles heel.
A blackstone UOA test will detect coolant problems alot sooner than the eyeball method. Save an oil sample from next oil change and send it to blackstone. And keep looking/checking for oil leaks from the cylinder head. Best done during sunny days.

Bought mine used with 7yr/100 k cpo warranty so im riding it out.

However, if i was in your position, I'd trade it in after lease and get a 2021 or older model(since they fixed the design and production problems associated with the cylinder head problems) or see if they'll CPO certify your current CX-9(CX-5) for 7 yr/100,000 miles instead of the 5 yr/60,000 mile.

Edit,:just an fyi, if youve hardly put any miles on it, problems might not crop up until after the warranty is up. More use means more mileage, more heat, more pressure, etc. Mileage and not age is very important for the problems to become known.
 
Last edited:
A blackstone UOA test will detect coolant problems alot sooner than the eyeball method. Save an oil sample from next oil change and send it to blackstone. And keep looking/checking for oil leaks from the cylinder head. Best done during sunny days.

Bought mine used with 7yr/100 k cpo warranty so im riding it out.

However, if i was in your position, I'd trade it in after lease and get a 2021 or older model(since they fixed the design and production problems associated with the cylinder head problems) or see if they'll CPO certify your current CX-9(CX-5) for 7 yr/100,000 miles instead of the 5 yr/60,000 mile.

Edit,:just an fyi, if youve hardly put any miles on it, problems might not crop up until after the warranty is up. More use means more mileage, more heat, more pressure, etc. Mileage and not age is very important for the problems to become known.

Thanks for this, looked at website but wondering if there's a Cdn company. Or i guess it doesn't matter, just mail it across border? Maybe some northerners can advise... @sm1ke I recall you send regularly, did you have a preferred lab in Canada?

I'm def crazy low milage, 17000ish km after 3 yrs. But next couple will be more normal for us, maybe 18-20k a yr. Sill, by lease end I won't be very high at all, so good to hear that's on my side.
Again, sorry for my lack of knowledge, if you can explain it to me like the idiot I am, to look for oil leaks at the cylinder head I'd need to first take the black cover off I assume? Tried a couple video searches but they mostly talk about how the turbo works. Don't worry about a long explanation, if it isn't something that can be described simply, it's probably beyond what I'll reliably be able to check anyway.

As much as I love the CX9, something like this would make me really pause at buyout. It's certainly not a car without flaws for our needs, and we don't usually keep cars very long. So it won't take much to tip the scales for me to look elsewhere. And the CX90 will be still relatively new in late 2024, so that will have it's own set of risks too even if I stayed with the brand.
 
I'm having doubts. Got mine just over 3 yrs ago, 2019 leased. Love it. Figured I'd buy it out after the 5 yr term ends, since the buyout prob will still be a deal compared to the market then.

I'm super low km as well, car has hardly moved in covid. So buying out seemed a no brainer.

Now I guess I'm glad that (I think?) my 5 yr lease coincides with my powertrain warranty. I'll be forced into a decision before my coverage runs out.

For anyone reading this, I'm pretty green wrt engine stuff, so I've looked at some of the advice here for detection. Smells, inspect levels in the tank (I'll look later to make sure I can even locate this tank), watch for puddling. Watch for fluid in engine bay where it's not supposed to be. Check dipstick. Seems this is all done best with engine cold?

Anyone have other advice? I do unfortunately tend to have a heavy foot and I also tow.

This wasn't the news I wanted, regardless of how rare it is. And yay for me, I also have a 17 CRV so engines are now my achilles heel.
I’m definitely selling it. I won’t take the chances. I drive around the Rockies. I don’t think mountain driving and the reference issue are compatible.
 
Big surprise. I just went outside to vacuum the car and the coolant tank is empty.
After getting my cx5 back from bodyshop, it was below min line...
I corrected and and am now watching level as well as getting blackstone reports.

Some evaporation is normal but if you are continuously losing more than an inch or two, then you need to get it checked out.
 
Thanks for this, looked at website but wondering if there's a Cdn company. Or i guess it doesn't matter, just mail it across border? Maybe some northerners can advise... @sm1ke I recall you send regularly, did you have a preferred lab in Canada?

Again, sorry for my lack of knowledge, if you can explain it to me like the idiot I am, to look for oil leaks at the cylinder head I'd need to first take the black cover off I assume? Tried a couple video searches but they mostly talk about how the turbo works. Don't worry about a long explanation, if it isn't something that can be described simply, it's probably beyond what I'll reliably be able to check anyway.

As much as I love the CX9, something like this would make me really pause at buyout. It's certainly not a car without flaws for our needs, and we don't usually keep cars very long. So it won't take much to tip the scales for me to look elsewhere. And the CX90 will be still relatively new in late 2024, so that will have it's own set of risks too even if I stayed with the brand.

So the labs I've used in the past were Bureau Veritas in Edmonton, and AGAT Labs in Calgary. I prefer AGAT Labs because they have a "shipping depot" in my city, and I could just leave the boxed and addressed sample with the depot and they would ship it to AGAT for free. You can do a search on their website to see if they have a shipping depot local to you, or you can email perrin@agatlabs.com and she might be able to assist. I haven't sent a report in for about a year and a half, so I'm not sure if anything has changed since then.

For this particular issue, the leak to look out for is a coolant leak. When the coolant that our engines use dries up, it leaves a bright green crusty residue. So if you have a spot where you usually park you car, keep an eye out for puddles of coolant directly underneath the engine. The coolant may also be visible on the plastic shielding underneath the engine, and dried coolant reside should be visible on the bottom of the engine block, towards the rear (closest to the firewall). I think you'll have to remove the plastic shielding underneath to see it though. I'm not sure if any leaks will be visible from a top-down look at the engine.

You should also be able to smell coolant if it is leaking, it's a very sweet scent.
 
Anyone have experience trading in a vehicle needing a new engine or transmission? Is it a simple value deduction of the repair cost or will the dealer take even more off the value than the repair because of the hassle?
I traded in my 2016 CX-9 with an active leak. I answered all their questions truthfully but did not offer any extra information. At first, it was a sight unseen offer (didn’t plan on buying when we visited). Showed up the following day and they did their inspection and did not find the coolant leak or did find it and didn’t care. Got average trade in estimate for it. K-seal was recommended to me by an older gentleman who said he used to work for a dealership that would throw that in any car that had a coolant leak. Not sure if it would work or the legality of that
A blackstone UOA test will detect coolant problems alot sooner than the eyeball method. Save an oil sample from next oil change and send it to blackstone.
This coolant leak issue is why I started getting oil sample analyses done every oil change. They never detected it. My nose detected it before anything else. Kind of sweet kind of warm celery smell when standing near the vehicle after turning the engine off.
 
Buy a Toyota? Actually, if there is a weak spot in a gasket or casting there's nothing that can be done. Keep an eye on the coolant level and get to the dealer if there is a loss. Look for antifreeze puddles under the car where you park. It'll be the same color as the antifreeze in the plastic overflow tank and feel a bit slippery, not completely watery.
Mazda vs, Toyota 2.5 (NA engines) are quite literally almost exactly the same.
 
Back