Tap a category to read its complaints. One report may name several components.
When problems were reported
Mileage at the reported incident
90–25K
1025–50K
650–75K
175–100K
3100–150K
0150K+
29 reports with mileage · 75 unknown
NHTSA’s mileage field refers to the reported incident, not necessarily the filing date. This shows report counts, not the likelihood of a failure.
What to inspect
Issues worth paying extra attention to based on owner reports.
Engine. Review the 65 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →
Electrical System. Review the 14 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →
Service Brakes. Review the 11 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →
NHTSA owner reports · September 18, 2026 snapshot.
3 crash reports1 fire reports2 injury reports
What owners actually said
104 reports
Mileage unknown · May 30, 2024
Engine And Engine Cooling
The contact owns a 2016 Mazda CX-9. The contact stated that while driving at an undisclosed speed, the vehicle stalled. Several unknown warning lights illuminated. The contact stated after the vehicle cooled off, the was able to be restarted. The contact checked under the vehicle and stated that there was coolant leaking on the …
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The contact owns a 2016 Mazda CX-9. The contact stated that while driving at an undisclosed speed, the vehicle stalled. Several unknown warning lights illuminated. The contact stated after the vehicle cooled off, the was able to be restarted. The contact checked under the vehicle and stated that there was coolant leaking on the ground. The vehicle was taken to an independent mechanic, where it was diagnosed with a coolant leak behind the engine. The vehicle was not repaired. The contact related the failure to Technical Service Bulletin: 01-002/23. The dealer referred the contact to the manufacturer for assistance. The contact was unable to reach the manufacturer for assistance. The failure mileage was unavailable.
NHTSA ODI #11591593
Mileage unknown · May 24, 2024
Engine
Vehicle had a horrible coolant leak at the rear of the engine to find out the engine has a weak cylinder head and is known to break and leak coolant. The vehicle will need a new cylinder head or engine replacement.
NHTSA ODI #11590677
Mileage unknown · May 21, 2024
Engine
A month ago, I experienced a coolant leak at the back of the engine compartment. Upon researching I found that the head was prone to crack at the turbo and produce the leak. I took to my dealer, and they confirmed that it was in fact a cracked head causing the coolant leak. They also confirmed it was a known Mazda problem on t…
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A month ago, I experienced a coolant leak at the back of the engine compartment. Upon researching I found that the head was prone to crack at the turbo and produce the leak. I took to my dealer, and they confirmed that it was in fact a cracked head causing the coolant leak. They also confirmed it was a known Mazda problem on the 2016 and newer 2.5 liter turbo engines. The dealer fixed four in the last month and one on a car their salesman purchased that the head failed at only 2000 miles. I was quoted a cost of $5965 for cylinder head replacement. It seems extremely excessive for a new cylinder head and a more appropriate price for a completely new motor. If this is a known defect on this motor no matter the miles, it seems Mazda should correct this problem in or out of warranty.
NHTSA ODI #11589984
Mileage unknown · May 14, 2024
Engine
Engine head cracked. Known problem with a tsb issued
NHTSA ODI #11588715
Mileage unknown · May 6, 2024
Engine
My car has a cracking cylinder head and is leaking coolant.
NHTSA ODI #11587338
Mileage unknown · Apr 28, 2024
Engine
2016 Mazda CX-9 2.5L Turbo Touring with 93,197 miles. In September of 2022, I noticed a sweet smell coming from the engine bay after coming home from work. I took my car to my mechanic on 9/30/2022 for an oil change and asked if they could figure out the "sweet smell" coming from the engine bay. When they were doing the oil ch…
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2016 Mazda CX-9 2.5L Turbo Touring with 93,197 miles. In September of 2022, I noticed a sweet smell coming from the engine bay after coming home from work. I took my car to my mechanic on 9/30/2022 for an oil change and asked if they could figure out the "sweet smell" coming from the engine bay. When they were doing the oil change, they checked for leaks and noticed that coolant was leaking from cylinder head. Since it was out of warranty, I had my mechanic repair the issue. Which resulted in a complete cylinder head replacement. This is a know issue by Mazda and there is lots of documentation online for this as well. There has since been updated parts to repair this issue, but this should be a recall covered by Mazda. Cause this repair cost me $5,700 out of pocket.
NHTSA ODI #11585709
Mileage unknown · Apr 12, 2024
Electrical SystemSeatsFire
My seat warmer caught fire and burnt a hole through the seat.
NHTSA ODI #11582514
Mileage unknown · Apr 11, 2024
Engine
We noticed anti-freeze leaking from our car a couple of days ago and immediately brought the car to our local mechanic. The mechanic determined that one of the cylinder heads in the engine was cracked and was leaking anti-freeze. He said the car was unsafe to drive. He also told us that a TSB had been issued by Mazda for this pr…
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We noticed anti-freeze leaking from our car a couple of days ago and immediately brought the car to our local mechanic. The mechanic determined that one of the cylinder heads in the engine was cracked and was leaking anti-freeze. He said the car was unsafe to drive. He also told us that a TSB had been issued by Mazda for this problem ( Bulletin No 01-002/23, issued 02/10/23). This bulletin states "Residual stress generated during production in the cylinder head material may be greater than expected. The external force from the exhaust system when driving over bumps may cause unexpected force to certain areas of the cylinder head". Had we not noticed the leak, the engine could have overheated, causing the engine to seize at any time, any place. which could have led to a dangerous accident. An accident that could have occurred on a major highway and could have involved other vehicles as well. Our car has just under 80,000 miles, has been well maintained and garage kept. I do not understand why a manufacturing defect such as this - which could lead to engine failure is not a mandatory recall by the manufacturer. We should have been warned that this could happen and mazda should be responsible for the cost of the repair. It is an engineering design flaw of the vehicle!
NHTSA ODI #11582438
Mileage unknown · Mar 18, 2024
Power TrainSuspension
I started smelling coolant after exiting the vehicle from a drive. Coolant level was very low. Adding coolant did not last long. I could not see where the leak was. The dealership evaluated and determined I had a cracked cylinder head and the car is leaking coolant near the rear of the engine. This could cause the engine to seiz…
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I started smelling coolant after exiting the vehicle from a drive. Coolant level was very low. Adding coolant did not last long. I could not see where the leak was. The dealership evaluated and determined I had a cracked cylinder head and the car is leaking coolant near the rear of the engine. This could cause the engine to seize should coolant get into the engine. The dealer (New Rochelle Mazda) explains the cylinder head needs replacing. The dealer also observed bad rear sway bar links. One was detached. The car is serviced at the same dealership every 5k miles. The car has approximately 85k miles. The cylinder head has been repaired by the dealer under the extended warranty. Safety risk was moderate as the car could have stalled on the highway. The component was inspected by the warranty company and dealer only. The only warning lamps that showed up once were both brake indicator lights came on and the climate control would not warm the car.
NHTSA ODI #11578122
Mileage unknown · Mar 4, 2024
EngineFuel/propulsion SystemVehicle Speed Control
Vehicle “surges” at idle. 300-500 RPMS at a time. Sometimes the brakes hold and sometimes not. Have nearly been in 3 collisions the last 2 days because of this issue. The ECM codes indicate throttle body or TPS issue, both of which have been unfounded. Vehicle has 63,000 miles. Researching this topic online found that many other…
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Vehicle “surges” at idle. 300-500 RPMS at a time. Sometimes the brakes hold and sometimes not. Have nearly been in 3 collisions the last 2 days because of this issue. The ECM codes indicate throttle body or TPS issue, both of which have been unfounded. Vehicle has 63,000 miles. Researching this topic online found that many others have had this issue with no associated safety recalls noted. I am hoping to bring light to this so someone doesn’t have to be injured or killed to have this rectified.
NHTSA ODI #11575368
Official recalls
0
No recalls in this snapshot.
Model-level recall history does not show whether a particular VIN is affected or has received a repair. Check a VIN with NHTSA ↗
NHTSA investigations
0
No exact-year investigations in this snapshot.
2016 Mazda CX-9 Problems, Complaints & Recalls | Skip That Year