CX-9 2.5T Engine Coolant Leaking TSB

[sm1ke]

I think that by now, they may have enough information to determine whether just the cylinder head and gasket need to be replaced, or whether the entire engine needs to be replaced.

If you want to get rid of a vehicle, now is the best time to do it. But try to make sure you have a replacement lined up, because while trade-in values have increased, so have selling prices (for the most part).

 

[Jack Rabbit]

From what i understand, the cracked cylinder head and coolant leaks is happening on CX5, CX9, 6, etc. on both the NACD(naturally aspirated cylinder deactivation) motors and the Turbos.

It sounds as if they replaced whole engines initially but now do just a cylinder head and gaskets replacement.

 

[sm1ke]

Full engine replacement now is likely determined by how severe the coolant leak is (if the engine is leaking coolant). Milky oil = engine replacement.

 

[youri]

It is in the TSB, they only change the cylinder head now unless there are signs of engine overheating or of coolant mixed with the oil.

They were changing the whole engine before while they were investigating the source of the problem, likely because they weren’t sure what repairs needed to be done, and because they were tearing down the engines to pinpoint the issue and come up with a solution and repair procedure.

Note that TSB says use a « modified cylinder head gasket », so it looks like they made changes to that part to try to resolve the issue.

https://static.nhtsa.gov/odi/tsbs/2022/MC-10215280-0001.pdf

1. Verify the customer concern.
2. Confirm the crack(s) and coolant leak(s) are located at the area(s) shown in the "Description" above:
- If the coolant leaks are coming from other than the cylinder head itself, this Service Information is not applicable.
Diagnose the leaks according to the instructions on MGSS online.
- If the coolant leaks are coming from the area(s) shown in the "Description" above, proceed to Step 3.
3. Inspect for DTC P111A:
- If DTC P111A is stored in memory, engine overheating is suspected. This Service Information is not applicable.
Diagnose the cause and repair, replacing the partial engine according to MGSS online. Contact MASH for partial engine approval.
- If DTC P111A is not stored in memory, proceed to Step 4.
4. Drain some engine oil into a container.
5. Inspect the color of the engine oil. Is it a milky light brown color indicating coolant is mixed in with it? - If Yes, this Service Information is not applicable. Contact MASH for partial engine approval.
- If No, proceed to Step 6.
6. Replace the cylinder head assembly with a new one using a modified exhaust manifold gasket according to the instructions on MGSS online:
NOTE: MASH approval is NOT required for cylinder head assembly replacement.
• CX-5: CYLINDER HEAD GASKET REPLACEMENT [SKYACTIV-G 2.5T]
• CX-9: CYLINDER HEAD GASKET REPLACEMENT [SKYACTIV-G 2.5T]
• Mazda6: CYLINDER HEAD GASKET REPLACEMENT [SKYACTIV-G 2.5T]

 

[DML]

Full engine replacement now is likely determined by how severe the coolant leak is (if the engine is leaking coolant). Milky oil = engine replacement.

Dropped off my 2017 CX9 at the delearshop for coolant leak and engine overheat after message poped up for low coolant level. Car is out of warranty. Mazda Canada is suggesting engine replacement @ just about 75,000 miles. They asked for vehicle maintenance history which I provided for a decision if they will be covering the replacement. 4 days gone, no news except further request on car maintenance history. Just readon this forum this is a known issue. Fingers crossed as I await their decision. Not ready to spend so much on an engine replacement

 

[crimeariver]

Dropped off my 2017 CX9 at the delearshop for coolant leak and engine overheat after message poped up for low coolant level. Car is out of warranty. Mazda Canada is suggesting engine replacement @ just about 75,000 miles. They asked for vehicle maintenance history which I provided for a decision if they will be covering the replacement. 4 days gone, no news except further request on car maintenance history. Just readon this forum this is a known issue. Fingers crossed as I await their decision. Not ready to spend so much on an engine replacement

Do you do the maintenance yourself? What form of confirmation did you provide?

 

[PTguy]

What maintenance would relate to a crack in the cylinder head metal? The coolant leak can be visually observed, according to photos I've seen, as dried green coolant on the back and bottom of the engine. That shows that a low coolant condition wasn't caused by anything else.

 

[Silly Wabbit]

What maintenance would relate to a crack in the cylinder head metal? The coolant leak can be visually observed, according to photos I've seen, as dried green coolant on the back and bottom of the engine. That shows that a low coolant condition wasn't caused by anything else.

Unfortunately unless you want to take them to court and question this, these are the stupid hoops you must jump thru to get claim approved. Next hoop is probably proof you've filled the tires to the factory psi to avoid excessive shock to the block.

 

[jal142]

What maintenance would relate to a crack in the cylinder head metal? The coolant leak can be visually observed, according to photos I've seen, as dried green coolant on the back and bottom of the engine. That shows that a low coolant condition wasn't caused by anything else.

The implication here is that "loyal customers" are more likely to get a goodwill repair. Mazda has been telling people with cracked heads to pound sand, and then justifying the decision by telling them they didn't have their regular maintenance done at the dealer.

 

[sm1ke]

The implication here is that "loyal customers" are more likely to get a goodwill repair. Mazda has been telling people with cracked heads to pound sand, and then justifying the decision by telling them they didn't have their regular maintenance done at the dealer.

I think that was only one person on these forums. I could be wrong..

 

[Jack Rabbit]

I think that was only one person on these forums. I could be wrong..

I thought i read more than one across the CX platform( cx5, Cx9,etc) that had difficulties getting engine head replacements after warranty regardless of whether over by days, weeks or months.

I agree with some of the above posters.

As far as i'm concerned, based of their refusal to even cover TCU and PCU updates during the 3 year bumper to bumper warranty period, I forsee a battle ahead for any engine or tranny repairs even during the powertrain warranty period and even with maintenance reciepts.

Imo, as more and more of these show up and it becomes more widespread , I see them circling the wagons and deny replacement/repairs and using every reason/excuse possible to victim blame the customer for the defect.

My opinions are based on my lifelong history of both common people, companys and even nations and their leaders refusing to take their share of responsibility for problems.

 

[sm1ke]

As far as i'm concerned, based of their refusal to even cover TCU and PCU updates during the 3 year bumper to bumper warranty period, I forsee a battle ahead for any engine or tranny repairs even during the powertrain warranty period and even with maintenance reciepts.

Imo, as more and more of these show up and it becomes more widespread , I see them circling the wagons and deny replacement/repairs and using every reason/excuse possible to victim blame the customer for the defect.

You may be right. Certainly a very negative, "doom and gloom" outlook, but at least you'll be prepared for such a response if it actually gets that bad. I don't think it will, but I guess time will tell as this all plays out.

 

[Kedis82ZE8]

TSB revision

https://static.nhtsa.gov/odi/tsbs/2023/MC-10230890-0001.pdf

 

[sm1ke]

Thanks for posting @Kedis82ZE8! Looks like the BOM on page 4 was revised.

 

[crikey]

Our 2019 Signature has approximately 23K miles and I don’t recall having seen a dashboard notification showing anything about the coolant. Has anyone just showed the TSB to the dealership and issue was addressed? Or does the vehicle need to be showing symptoms? The VIN does fall in the list of affected vehicles. Thanks.

 

[yrwei52]

Our 2019 Signature has approximately 23K miles and I don’t recall having seen a dashboard notification showing anything about the coolant. Has anyone just showed the TSB to the dealership and issue was addressed? Or does the vehicle need to be showing symptoms? The VIN does fall in the list of affected vehicles. Thanks.

A TSB isn’t a recall. And yes your 2.5T does need to show coolant leak symptom or the Mazda dealer won’t do anything for you. You sure can present the TSB in your next visit to your Mazda dealer and ask them to check if there’s any sign of cracked cylinder head.

 

[sm1ke]

Our 2019 Signature has approximately 23K miles and I don’t recall having seen a dashboard notification showing anything about the coolant. Has anyone just showed the TSB to the dealership and issue was addressed? Or does the vehicle need to be showing symptoms? The VIN does fall in the list of affected vehicles. Thanks.

A TSB is a document that is meant to be used by service techs as a point of reference for known issues. If your vehicle isn't showing symptoms, there's no issue to address. Just keep an eye out for the typical symptoms of an external coolant leak - green fluid leaking on to floor underneath the engine, a sweet smelling odor coming from the engine bay, and a low coolant level. If you notice any of those symptoms, report them to the dealer and reference the TSB.

 

[crikey]

Thanks, guys. I’ll keep an eye out on it, and also have the dealership check on my next oil change.

 

[ctbale]

CX9 Built Jan 2021. Many months after the vin range for coolant leaks for cracked heads. This was on Facebook. This guys car should have had the updated head but it cracked. I spent a ton of time looking at his head and the tsb and the heads look the same. Maybe Mazda just put in deeper exhaust studs? I know the exhaust gasket was claimed in the TSB to have been revised also. Anybody know?

 

[youri]

I don’t know if it is a typo, but a 2020 cx-9 built in 2021? I would expect a 2020 cx-9 to being built in 2019 or early 2020. Maybe it is a 2021 CX-9 built in 2020?

That would change whether it has the updated head or not.