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
Just saw this post and thought I would add on. We were one of the early ones to get the engine in October 2019 on our 2019 model. It got hot and light came on and my wife stopped. It happened again and she parked it. I added ~pint of distilled water and took it to the dealership and it was running perfect at the time. They stated the engine had to be replaced at no fault of our own. It only had about 10-15k miles give or take (if that). Mazda dealership gave us a loaner and ordered it and put it in on their dime. We had to go back one time as they forgot to torque down one of the bolts (poop happens), but they fixed that and we have been fine ever since. We are at 51k now.
 
Just saw this post and thought I would add on. We were one of the early ones to get the engine in October 2019 on our 2019 model. It got hot and light came on and my wife stopped. It happened again and she parked it. I added ~pint of distilled water and took it to the dealership and it was running perfect at the time. They stated the engine had to be replaced at no fault of our own. It only had about 10-15k miles give or take (if that). Mazda dealership gave us a loaner and ordered it and put it in on their dime. We had to go back one time as they forgot to torque down one of the bolts (poop happens), but they fixed that and we have been fine ever since. We are at 51k now.
Sorry correction ours is a 2018 NOT 2019 ( my truck is a 2019…oops)
 
I've continuously been following this thread and monitoring this situation now for months and I just wanted to update on some research of my own here in Canada. I have yet to come across a failure in my area on a Gen 2 CX-9 or any other Mazda model equipped with the 2.5T, granted, my sample size has been fairly small as my area isn't large, but I have a good relationship with the Parts Manager at my dealer and everytime I see him when I go in to pick up parts (filters etc.) I inquire about it or any details he may have heard. So far he's heard nothing. I'm still thinking that this issue isn't widespread enough YET for Mazda North America to be concerned.

My personal plan with my 2021 CX-5 Signature is to ride it out for the next 5 years since in Canada the Powertrain Warranty is 5 Years/Unlimited KM and see what happens. I service my own vehicles so I keep a close eye on my vehicle and regularly inspect for any leaks. For anyone else doing their own work or not going to the dealership for service I would advise keeping all your receipts and document all your services. Keeping my fingers crossed. 🤞
 
So I'm on the phone with Mazda of North America. They dug deeper into the order for my engine, and the estimated arrival date has changed now to December 8. So it's slipped a few weeks from their "mid-November" estimate. I'm still on hold, so we'll see what they can do, but I'm not optimistic.
 
So I'm on the phone with Mazda of North America. They dug deeper into the order for my engine, and the estimated arrival date has changed now to December 8. So it's slipped a few weeks from their "mid-November" estimate. I'm still on hold, so we'll see what they can do, but I'm not optimistic.
They told me they’re trying to expedite my parts with a “CEO order” but that they’re not sure. December 8 was stated as a very rough estimate for delivery and was not a confident estimate at all.
 
Hello! I'm joining the party!

I rolled 65K this past weekend and did my standard 5K mile oil change.

I noted a strong scent of coolant (sweet, syrupy, etc.) while standing outside the car with the engine idling.
I noted a dark green and whitish residue all over the oil filter and surrounding components.
I noted a lack of coolant in the reservoir and low coolant in the radiator.

I hauled it in for diagnosis this morning.

The cooling system is not holding pressure and is leaking a tremendous amount of coolant at the rear of the engine. Preliminary diagnosis is a crack in the cylinder head, however I have not been provided pictures of the damage.
The dealership may need to pressure wash the engine to find the exact point of the leak, as I took the CX-9 camping a few months ago and there was a bit of muck and mud in the engine bay.
The dealership is pressing for a full long block for some reason. (Not sure why not just a cylinder head.) Luckily, I have an extended warranty that covers me up to 110K miles.
 
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They told me they’re trying to expedite my parts with a “CEO order” but that they’re not sure. December 8 was stated as a very rough estimate for delivery and was not a confident estimate at all.
I saw earlier in the thread that you are/were in the Washington DC area.

I'm in Manassas and my CX-9 was purchased at (and being worked on at) Brown's Chantilly Mazda.

Are you still in the DC area or are you some 2700 miles away.

If you need anyone in the area to assist with loading the repaired vehicle up on a shipper's truck, I can help out with that.
 
I saw earlier in the thread that you are/were in the Washington DC area.

I'm in Manassas and my CX-9 was purchased at (and being worked on at) Brown's Chantilly Mazda.

Are you still in the DC area or are you some 2700 miles away.

If you need anyone in the area to assist with loading the repaired vehicle up on a shipper's truck, I can help out with that.
I’m still in the area for now. Even with the slip to December, it should be fine for my move. I have a family vacation it’s ruining but Mazda of NA is trying to help with that.
 
Hello! I'm joining the party!

I rolled 65K this past weekend and did my standard 5K mile oil change.

I noted a strong scent of coolant (sweet, syrupy, etc.) while standing outside the car with the engine idling.
I noted a dark green and whitish residue all over the oil filter and surrounding components.
I noted a lack of coolant in the reservoir and low coolant in the radiator.

I hauled it in for diagnosis this morning.

The cooling system is not holding pressure and is leaking a tremendous amount of coolant at the rear of the engine. Preliminary diagnosis is a crack in the cylinder head, however I have not been provided pictures of the damage.
The dealership may need to pressure wash the engine to find the exact point of the leak, as I took the CX-9 camping a few months ago and there was a bit of muck and mud in the engine bay.
Sorry to hear that. I began to feel this coolant leak issue is a design flaw on the engine block. But why the same problem isn’t happening on the 2.5L, to me still is a mystery.


The dealership is pressing for a full long block for some reason. (Not sure why not just a cylinder head.) Luckily, I have an extended warranty that covers me up to 110K miles.
Based on description of other victims, the culprit seems to be from cracked cylinder block on the back side. The whole engine (long block) is needed. Please keep us updated on your situation, and how long does it take to get a new engine.

At least you have an extended warranty which covers engine replacement which is good. One case who has the extended warranty but the company refused to cover the engine replacement with a strange reason.
 
The dealership is pressing for a full long block for some reason. (Not sure why not just a cylinder head.)
This seems to be the solution provided by Mazda for the fix. My dealer originally was going to do the short block and Mazda corrected them and now they're doing the long block. From what I gather, it's probably better this way to avoid having dealer techs working in the inner workings on the engine in ways where they're probably not as savvy? Someone else can fill me in on this one, but when I mentioned the short block replacement, various folks chimed in and said they wouldn't trust the dealer to execute that properly.
 
Sorry to hear that. I began to feel this coolant leak issue is a design flaw on the engine block. But why the same problem isn’t happening on the 2.5L, to me still is a mystery.

My guess is the addition of the turbo = extra heat.

I have oldschool experience with turbos, so I make it a point to let my cx9 idle a few seconds before shutting it off. (Friendly reminder: don't do this in an enclosed garage! lol)

I think there was someone here who posted a photo of broken Mazda engines from the dealership which included the NA engine..
 
If it's only a matter of time until every 2.5T has to be replaced, I don't know how Mazda absorbs all that cost and producing all those replacement engines. There's going to be severe damage to their bottom line, at a time when capital is needed to compete with a quickly changing auto industry. Plus, those replacement engines will have to be made after Mazda isn't even making them anymore for new models (with the inline 6 coming).
 
New engine gang!

PYZ3-02A-300D is on my parts list:


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"I have oldschool experience with turbos, so I make it a point to let my cx9 idle a few seconds before shutting it off."
That is a good plan, but I don't think it relates to these coolant leaks. A turbocharger is a gas turbine with a centrifugal air compressor on the same shaft. The hot exhaust gas spins the gas turbine section, the shaft spins the air compressor, and the compressor pumps more air into the engine's induction system so it can burn more fuel with the correct fuel to air ratio. The heat from the hot exhaust gas gets the turbo part so hot that if shut off right after a hot, heavy run the oil can bake to carbon and damage bearings and seals. That's why the short cool-down period with the engine idling works, the circulating oil and coolant carries the excess heat away. I don't tow or carry heavy loads, so the main time I think about a cool down is when pulling directly into a highway rest stop after a high speed run.
 
I also let the engine cool down after a hard run. (And I worked that b**** pretty hard.) It seems that it is a casting issue in the engine block and/or cylinder head.

The cooling of a turbocharger is directly related to coking of the oil on the fluid bearing of the turbo.
 
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