2016~2021 Engine coolant leak

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2007 Mazda CX-9 Touring
It was much cheaper for them to go with a low mileage engine. I can't believe the prices i saw on the internet for used engines for a 2016. They had one with only 7k miles for 2500. That's pretty good if you ask me. The first gens are more expensive with high miles.
 
I don't know the details, but the repair shop initially thought it was just the gasket and when they started taking the engine apart they recommended replacing the long engine block. It was also looked at by the extended warranty person, and we all know they try to get out of paying for anything, so it must have been a legitimate issue. The car was built 4/2016.
 
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2010 CX-9 GT
Replacing the long block would point to the head and block warping so much that they couldn't be machined flat without removing too much material. Or, there were cracks in the head/block.

Either way, that's troubling if it is what happened....
 
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2005 Mazda3
I don't know the details, but the repair shop initially thought it was just the gasket and when they started taking the engine apart they recommended replacing the long engine block. It was also looked at by the extended warranty person, and we all know they try to get out of paying for anything, so it must have been a legitimate issue. The car was built 4/2016.

Any updates on your situation? Did you get the block replaced?
 
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2005 Mazda3
Yes, they actually ended up replacing the entire engine.

Ah gotcha, thanks, sorry I missed it up there, re-read that they were going to swap in that lower mileage motor.

Just an update, after more digging around the entire engine was replaced. Thank God I had that extended warranty as the job would have cost around ~$8000. I was hoping to get a brand new engine, but unfortunately the third party warranty company didn't want to pay for a new one. However the engine they found only had 29,000 miles on it, compared to my 80,000 miles. Also they looked over the engine, replaced all the gaskets and moved my new spark plugs from the old engine to the new one. Not too shabby.

Hope that motor lasts you a good long trouble free time.
 
Well looks like the same thing just happened to me, as I came across this forum last week as I was looking at possibilities of my coolant leak issue. I have a 2016 Mazda CX-9 Signature and I just hit 60k this week, I started noticing issues about 3 weeks ago when I had an engine hot light come on when I was siting in a parking lot with my air conditioner on. Once the car started to move it went away. When I got home and let the engine cool down I noticed my reservoir for coolant was low, so I added about one gallon. I did not see any issues again for another week or so, but noticed small puddles of coolant under the car from time to time. I called and made an appointment with the dealership and explained my issues. the day before going to my appointment my engine hot light came on a few times when ever I was below 35 MPH, and I was not getting any heat from the left side of my vents for defog, it would come out cold when set at 85 deg. I figured this could be a fan or water pump issue as the bearings might work when at higher rpms. I made it to the dealership with out any issues or breaking down as this had progressed quickly over a two week period. The final verdict was the engine seemed to be cracked and leaking. This was on Saturday morning 9/19/20. Since I just hit 60k miles, and the problem started happening before this happened I am being told it should be covered under the warranty. Also I was told that this is an known issue with my year and model. I was given a loaner for now as they have to complete a full report and submit. I was told they will have to replace the engine. Waiting for further information with my fingers crossed. I will post what the outcome is and the time line to get repaired.
 
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2010 CX-9 GT
That's the first one of these where we got a definitive explanation: cracked block.

Which seems odd, to be honest. I'm wondering if there was a casting issue with a certain batch of blocks or something. Other manufacturers have had porosity problems with certain engines.
 
I have the same problem and I put some liquid moly coolant additive so it cal hold some time... Mazda told me its a blind plug thread that is leaking... They want to replace engine at my expense because it have 4 month out of warranty and factory didnt aproved the change... Sorry for my english...
 
I just got back from the dealer and they’ll be replacing my engine. Leaking coolant and even showed me where it was coming from.
84k miles on mine. Bought it CPO from the dealer. Glad it came with extended warranty. Let’s see how long this takes as the engines are on back order
 
I just got back from the dealer and they’ll be replacing my engine. Leaking coolant and even showed me where it was coming from.
84k miles on mine. Bought it CPO from the dealer. Glad it came with extended warranty. Let’s see how long this takes as the engines are on back order
Good to hear you are fully under warranty. I was not as lucky but still didn't get fully charged. This will definatly make me consider my next purchase from Mazda. Looking to see how the newer models do. Good luck with the fix. Hope you got a nice new temp to ride around in.
 
Good to hear you are fully under warranty. I was not as lucky but still didn't get fully charged. This will definatly make me consider my next purchase from Mazda. Looking to see how the newer models do. Good luck with the fix. Hope you got a nice new temp to ride around in.
I got a 2021 CX-30. It’s so tiny.
 
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2017 CX9 GT AWD
I just got back from the dealer and they’ll be replacing my engine. Leaking coolant and even showed me where it was coming from.
84k miles on mine. Bought it CPO from the dealer. Glad it came with extended warranty. Let’s see how long this takes as the engines are on back order
If you haven't done so already, don't forget to take this poll regarding the coolant lead/engine replacement issue: https://www.mazdas247.com/forum/ind...cement-what-can-be-done-to-prevent.123875515/