TireKick

Model-year record

2018 Mazda CX-9
Image: Wikimedia Commons contributor · See source file

2018 Mazda CX-9

See the complaints, recalls, crash rating, and fuel economy in the public record. Then check the mileage and history of the car you found.

This page shows records, not a buy or avoid call.

The same model year can include a well-kept car and a neglected one. Use these records to plan what to check. Use the specific-car check when you know the mileage.

Complaints filed

125

Reports to NHTSA, 2018

Safety recalls

2

NHTSA campaigns on record

NHTSA crash test

Overall NCAP rating

Combined MPG

23.5

EPA estimate

Known issues

Engine issues lead owner complaints (48% of 125 reports), followed by unknown or other (14%).

Engine48% · 60 reports
Unknown Or Other14% · 17 reports
Electrical System10% · 13 reports
Power Train10% · 12 reports
Service Brakes4% · 5 reports
Steering2% · 3 reports
Air Bags2% · 2 reports
Engine And Engine Cooling2% · 2 reports

+ 8 more component categories with fewer reports.

Share of all 125 NHTSA complaints for this model year, grouped by the component owners named. Bars are scaled to the largest category. Examples: ODI 11750583, ODI 11742255, ODI 11716057, ODI 11681066, ODI 11674928.

Individual complaint reports(125)

Showing the 50 most recent reports
EngineJul 2026 · ODI 11750583Details +

The cylinder head on this 2018 Mazda CX-9 (Skyactiv-G 2.5T engine) cracked, allowing engine coolant to leak and intermix with engine oil, causing loss of coolant and catastrophic engine failure. The vehicle became undriveable in the first week of November 2025 at approximately 125,019 miles and has remained inoperable since; it was not in a crash and had to be towed. This matches a known, documented defect on Mazda's Skyactiv-G 2.5T engine: coolant leakage at the cylinder head near the exhaust manifold, leading to overheating and engine failure. Mazda issued technical service bulletin(s) addressing cylinder-head cracking and coolant intrusion, revised the cylinder-head casting (a superseding part number), and extended warranty coverage (program CSP11) for this specific concern. This vehicle fell just past the mileage cap of that extension. Safety risk: a cracked cylinder head causing coolant loss and engine overheating can produce sudden loss of engine power and overheating if it occurs while driving. No crash, fire, or injury resulted in this case. A formal dealer diagnosis is pending; the failed engine/cylinder head is being preserved and is available for inspection on request.

Reported
Jul 2026
Incident date
Nov 2025
Mileage
Not provided
Outcome flags
None reported
Open ODI 11750583 at NHTSA →
SeatsJun 2026 · ODI 11742848Details +

My passenger heated seats malfunction while I was driving. As I was driving on the highway I smelled something burning. I didn't know where the smell was coming from it was strong . Then while I'm driving on the highway my seat started to smoke a lot I got scared and pulled on side of the road. I realized my seat was the issue turned off the heated seats on the control. Step out the vehicle on side the highway I was nervous and scared standing outside my vehicle. The smoke eventually died down and cleared out. I never turned it back on and put a small piece of tape over the hole it burned through my seat.

Reported
Jun 2026
Incident date
Feb 2026
Mileage
Not provided
Outcome flags
None reported
Open ODI 11742848 at NHTSA →
EngineJun 2026 · ODI 11742255Details +

My wife was driving the vehicle when the emergency lights started going off. She had to pull over because the car wouldn't run and said it was overheated. All the maintenance has been done to the car. We took it to the dealership and they said it is a cracked head and it is a known issue. They even issued a extended warranty for it. It is TSB 01-002/23. There should be a recall on this not just a partial credit.

Reported
Jun 2026
Incident date
May 2026
Mileage
Not provided
Outcome flags
None reported
Open ODI 11742255 at NHTSA →
Power TrainApr 2026 · ODI 11731137Details +

My 2018 Mazda CX-9 with the SKYACTIV-G 2.5T engine has been diagnosed with a cracked cylinder head, cracked exhaust manifold, and cracked turbocharger at approximately 88,000 miles. This is a known design defect documented in Mazda TSB 01-002/23 and addressed by Customer Service Program CSP11, which extended the powertrain warranty to 10 years/120,000 miles for coolant leaks at the cylinder head. The TSB identifies exhaust manifold deformation and residual production stress as root causes of the cylinder head cracking. In my vehicle, the failure has extended to the exhaust manifold and turbocharger, both directly mounted to the cylinder head in the same high-stress zone. The turbocharger on this engine is a coolant-cooled unit. As coolant leaks from the cracked cylinder head, the turbocharger is deprived of its cooling supply, leading to excessive heat buildup and eventual cracking of the turbo housing. The turbo damage is a direct consequence of the cylinder head defect Mazda has already acknowledged. CSP11 covers the cylinder head but does not address consequential damage to the exhaust manifold and turbocharger caused by the same defect. I am requesting the NHTSA investigate whether Mazda's remedy is sufficient and whether a formal recall is warranted given the risk of sudden engine failure at highway speeds.

Reported
Apr 2026
Incident date
Apr 2026
Mileage
Not provided
Outcome flags
None reported
Open ODI 11731137 at NHTSA →
Electrical SystemMar 2026 · ODI 11725165Details +

The liftgate (trunk) opens sporadically. The system keeps trying to open the truck and it's causing a parasitic drain on my battery. I was stranded 2 hours from my home due to this. My trunk would sporadically beep three times, that is the only warning I received. There are safety recalls for other year of Mazda cx-9 but not my specific even though I am having the same issue.

Reported
Mar 2026
Incident date
Mar 2026
Mileage
Not provided
Outcome flags
None reported
Open ODI 11725165 at NHTSA →
Service BrakesMar 2026 · ODI 11723876Details +

My 2018 Mazda CX-9 experienced catastrophic engine damage after a radiator failure allowed coolant to enter the engine. The vehicle provided no dashboard warning, overheating alert, or coolant warning before the failure occurred. Modern vehicles are designed to alert drivers to overheating or cooling system failures. The lack of warning prevented me from addressing the issue and resulted in catastrophic engine damage. I believe this represents a potential safety defect in the vehicle’s cooling system monitoring and warning system.

Reported
Mar 2026
Incident date
Feb 2026
Mileage
Not provided
Outcome flags
None reported
Open ODI 11723876 at NHTSA →
SeatsFeb 2026 · ODI 11719629Details +

The adjustable rails holding the rear left seat in place no longer latch. It is available for inspection. This is the most common place for a car seat in this car. In the event of a crash the seat would slide forward. The seat belt attaches to the seat so there would be little restraint on the rear passenger. The mechanic who attempted a repair stated Mazda does not sell this part, only sells a replacement for the entire seat, about $5000. There were no symptoms, when adjusting the seat the rail just stopped holding the seat firmly in place when the adjusting bar was released.

Reported
Feb 2026
Incident date
Feb 2026
Mileage
Not provided
Outcome flags
None reported
Open ODI 11719629 at NHTSA →
EngineFeb 2026 · ODI 11716057Details +

Here the facts, bought a car out of state (Illinois) from Iowa with 130,131 miles on Sept 12th 2025, Mazda CX9, the dealer did not disclose any problems with the car, after 3 months of ownership, the car overheats on highway whit family including a [XXX] infant, white smoke under the hood and exhaust pipe, towed home, radiator was replaced, few days after that a coolant leak, vehicle was sent to an authorized Mazda dealership for diagnose, the technician told us, according to Mazda procedures, a cod P111A, the vehicle's engine reached unsafe level of temperature and the whole engine needs to be replaced because a cracked head cylinder. This problem is well known by Mazda because they addressed on a TSB01-002/23 and CSP11 extended warranty, there is a flaw in the design of the engine near the cylinders manifold area, that cracks the engine and requires a full replacement of the engine. its just a flaw in the design of the engine. This issue can appear at any point threatening the life of the occupants of the vehicle INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Reported
Feb 2026
Incident date
Dec 2025
Mileage
Not provided
Outcome flags
None reported
Open ODI 11716057 at NHTSA →
Electrical SystemJan 2026 · ODI 11713860 · fireDetails +

Passenger seat heater either had a grounding issue or shorted out, causing to seat to start smoldering and catching fire, destroying the seat. There has been recalls and lawsuits for this specific issue on this model in other years, but not for this model year.

Reported
Jan 2026
Incident date
Jan 2026
Mileage
Not provided
Outcome flags
Fire
Open ODI 11713860 at NHTSA →
Visibility/WiperOct 2025 · ODI 11694595Details +

Passenger side sun visor will not stay in place. Cannot lock it in up position, which means it droops. Causing sight of vision impairment.

Reported
Oct 2025
Incident date
Aug 2025
Mileage
Not provided
Outcome flags
None reported
Open ODI 11694595 at NHTSA →
Electrical SystemSep 2025 · ODI 11686751Details +

[XXX] 2018 MAZDA CX-9 GRAND TOURING 89014 MILES Date: 9/11/2025 To: Mazda North American Operations Attn: Customer Experience Center 7755 Irvine Center Drive Irvine, CA 92618 USA Subject: Formal Complaint Regarding Safety and Technical Issue – 2018 Mazda CX-9 Dear Mazda Customer Experience Team, I am writing to formally lodge a complaint regarding a serious safety and technical issue I have experienced with my 2018 Mazda CX-9. After a recent inspection conducted by Mazda Koch 33, it was brought to my attention that the engine wiring harness is defective and may potentially cause a fire or result in burns, posing a severe safety risk to me, my passengers, and others on the road. This issue is deeply concerning and unacceptable, especially considering Mazda’s reputation for reliability and safety. A fault in the engine wiring harness, particularly one that has the potential to ignite or burn, should be treated with the utmost urgency. It is troubling that such a critical component could present such danger. My vehicle has been serviced and maintained regularly, and I was not made aware of any recall or technical service bulletin that addressed this defect until the inspection. Given the nature of the defect, I believe this may be a manufacturer defect, and I request that Mazda: Immediately investigate and confirm whether this issue falls under an existing recall or known defect. Take full responsibility for replacing or repairing the affected wiring harness at no cost to me. Provide assurances in writing that my vehicle is safe to operate. Offer compensation or a loaner vehicle if the repair process renders my vehicle unusable for any period of time. Please consider this a formal request for immediate corrective action. I expect a prompt response within 10 business days of the date of this letter. If I do not receive a satisfactory resolution, I will be compelled to escalate this matter further through consumer protection agencies, such as the INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Reported
Sep 2025
Incident date
Sep 2025
Mileage
Not provided
Outcome flags
None reported
Open ODI 11686751 at NHTSA →
Power TrainSep 2025 · ODI 11685844Details +

my 2018 MAZDA CX-9 safety issue SCBS / SBS, LAS / LDWS, MASTER AND/OR HBC WARNING LIGHTS Forward sensing camera (FSC) stops functioning cause my car run rough even depress accelration and those light came on dashbaord -Forworad smart city brake support malfunction -smart brake system -front camera sensor malfunction

Reported
Sep 2025
Incident date
Sep 2025
Mileage
Not provided
Outcome flags
None reported
Open ODI 11685844 at NHTSA →
Electrical SystemAug 2025 · ODI 11682407Details +

I am submitting this recall request because my vehicle has experienced repeated incidents of a serious safety issue. While driving—most often on the highway—a warning appears that says “Smart System Brake Malfunction.” Immediately after, the car begins braking on its own without driver input. This has happened multiple times and, based on online reports, it appears to be affecting many Mazda vehicles across different models and years. Each time, I have been forced to pull over, turn off the car, and restart it to temporarily resolve the issue. This is extremely dangerous, especially at highway speeds, as it creates a high risk of rear-end collisions and sudden loss of vehicle control. When reported to Mazda, the concern was dismissed as a “sensor issue,” but the repeated nature and widespread reports suggest a potential systemic defect that requires urgent investigation and recall.

Reported
Aug 2025
Incident date
Aug 2025
Mileage
Not provided
Outcome flags
None reported
Open ODI 11682407 at NHTSA →
EngineAug 2025 · ODI 11681066Details +

Cracked cylinder head/leaking coolant.

Reported
Aug 2025
Incident date
Jul 2025
Mileage
Not provided
Outcome flags
None reported
Open ODI 11681066 at NHTSA →
EngineJul 2025 · ODI 11674928Details +

. In January 2024, I purchased a used 2018 Mazda CX-9. The vehicle ran well until [XXX], when I discovered an engine coolant leak. My mechanic diagnosed it as a known defect involving the cylinder head. My husband contacted Mazda Customer Service (CS), and they advised us to get an official diagnosis from a Mazda dealer. We brought the car to Orland Park Mazda, where a diagnostic confirmed the defect (report attached). We later received an email from Mazda CS saying that since our car was at the dealership, Mazda would take the lead in submitting the goodwill repair claim (email attached). When we followed up with Orland Park Mazda, they informed us that no one from Mazda CS had contacted them to authorize the repair. We relayed this to Mazda CS and gave them the direct number of our service advisor, Adrian. Mazda CS said they would follow up and get back to us within 48–72 hours. On a follow-up call, I spoke with Nancy at Mazda CS, who again told me that our case manager Cindy would contact us within 48–72 hours. Instead, we received an email denying the repair, stating the vehicle exceeded the 120,000-mile limit for the extended warranty (our vehicle has 133,500 miles). While our car is outside the warranty period, this is a textbook case of a well-documented defect covered under TSBs for the 2018 CX-9. Mazda has previously approved goodwill engine replacements for other customers well beyond this mileage. We are seeking fairness and consistency in handling known product defects. Our request is that Mazda approve the engine repair under goodwill coverage as they have in many similar cases. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Reported
Jul 2025
Incident date
Jun 2025
Mileage
Not provided
Outcome flags
None reported
Open ODI 11674928 at NHTSA →
Electrical SystemJul 2025 · ODI 11673548Details +

Infotainment screen (LCD) of Mazda CX-9 2018 has developed what looks like discoloration/scratching/frost in corner of screen about 2 years ago and it is continuing to spread over last 6 months. This screen is used for hands-free bluetooth/calling (which is now the law in Iowa) and the back-up camera which allows for safe backing. If screen is unreadable, these safety functions cannot be performed properly. I take my car into Mazda dealership for maintenance/oil changes and it has never been addressed as an issue, but I'm concerned.

Reported
Jul 2025
Incident date
Dec 2022
Mileage
Not provided
Outcome flags
None reported
Open ODI 11673548 at NHTSA →
EngineApr 2025 · ODI 11657829Details +

Our Mazda CX-9, having roughly 86,000 miles, had catastrophic engine failure while driving. This is caused by coolant leaking at the cylinder head and around the exhaust manifold. This in turn caused a crack in the engine block. Mazda refused to fix this as it wasn’t a “recall” and only a tsb sent out. 1000 of people have reported this issue, causing failure while driving but Mazda will not recall the engines nor fix them under an extended warranty. After a 4 month battle with Mazda they refused to fix this in our car even though they know the engine is a bad manufacturing issue. A recall needs to be made and Mazda needs held accountable. Our exact cause was exactly what the TSB stated but Mazda stated our crack was not in the correct spot. They need a recall covering all engine block cracks due to faulty manufacturing

Reported
Apr 2025
Incident date
Dec 2024
Mileage
Not provided
Outcome flags
None reported
Open ODI 11657829 at NHTSA →
EngineApr 2025 · ODI 11654683Details +

coolant leaking from engine block cracked cylinder head

Reported
Apr 2025
Incident date
Dec 2024
Mileage
Not provided
Outcome flags
None reported
Open ODI 11654683 at NHTSA →
Unknown Or OtherApr 2025 · ODI 11654693Details +

1. The navigation has a frosted crackle appearance framing the screen. It is difficult to read the navigation when needed. I know this has happened to other models of this vehicle and those were recalled and covered. 2. The brake senor keeps going off stating "SMART BRAKE SYSTEM MALFUNCTION". This goes off repeatedly while driving. 3. Then a second message pops up and reads "FRONT RADAR SENSOR SYSTEM MALFUNTION".

Reported
Apr 2025
Incident date
Apr 2025
Mileage
Not provided
Outcome flags
None reported
Open ODI 11654693 at NHTSA →
SteeringDec 2024 · ODI 11630249Details +

Steering makes knocking noises when turning. It happened suddenly with no damage to car to cause it. It was fine prior to parking, when the car was restarted and the wheel was turned knocking noise started. Mechanic found there is a tsb for this problem but no recall.

Reported
Dec 2024
Incident date
Oct 2024
Mileage
Not provided
Outcome flags
None reported
Open ODI 11630249 at NHTSA →
EngineNov 2024 · ODI 11624426Details +

Fan is not working and car is overheating when driving in traffic or low speeds - from forums this seems to be a common issue with this make/model and year

Reported
Nov 2024
Incident date
Oct 2024
Mileage
Not provided
Outcome flags
None reported
Open ODI 11624426 at NHTSA →
EngineNov 2024 · ODI 11624296Details +

coolant leaks at the cylinder head around the exhaust manifold. Caused crack in the head. The Mazda 2.5t engine has this common issue that Mazda knows about. Mazda has a bulletin out but has not issued a recall. Car over heated and I was left stranded. Took car to mechanic who says I need to replace my entire engine.

Reported
Nov 2024
Incident date
Nov 2024
Mileage
Not provided
Outcome flags
None reported
Open ODI 11624296 at NHTSA →
EngineOct 2024 · ODI 11622142Details +

My vehicle was low on antifreeze. I brought it into the dealer and had them look at it. They told me there was an antifreeze leak inside the engine. I told them, I think there's a service bulletin on it. TSB-01-013-21 And there are updates to it. They told me that the antifreeze leak does not pertain to this service bulletin. I told them, how can that be? When it's an antifreeze leak with an engine that only has 66000 miles on it so far. I spoke to mazda customer service in California They said the dealer is trying to get some financial relief for me to replace a $10000 engine. Which they said is on back order till march 2025. I said how can this leak not be a problem when the engine is on back order, I feel that this should not have happened With a engine, that has 66000 miles on it? And it should be fixed free of charge because antifreeze leak is a known problem with these engines since 2016, and they never notified me to bring it in and have the defective part fixed Which causes the antifreeze leak. If they did that, my engine would not have blown and would not need replacement. I'm hoping they understand and do the right thing and fix this.

Reported
Oct 2024
Incident date
Oct 2024
Mileage
Not provided
Outcome flags
None reported
Open ODI 11622142 at NHTSA →
EngineOct 2024 · ODI 11620834Details +

I purchased a 2018 Mazda cx9 from a local used car dealer several weeks ago. Check engine light came on after a few weeks for cylinder 3 misfire and there was a steep decline of the vehicle performance (hard start, rough idle, lower mpg, sluggish driving). Took it to Berge Mazda who charged me for diagnostics/spark plugs, and ignition coil. They informed me the next steps were a compression tests, fuel injectors and if that didn’t fix the problem then they wanted to strip down the engine to evaluate the cylinder head. At this point I decided to take it to my local mechanic who I trust, he diagnosed a cracked cylinder head. Now I’m stuck with a car I just bought that’s unsafe to drive needing a 6-8k repair. Upon further research there is a widespread problem with Mazda’s manufacturing of there cylinder heads on certain models (including the 2018 Mazda cx9). This is confirmed by TSB’s from Mazda along with a class action lawsuit recently filed. Upon more research on my vehicles history, I gathered that my vehicle was traded into Horne Mazda and then a couple days later auctioned to the used car dealer I bought it from. The fact that Mazda is selling off their own defective vehicles that are unsafe at auctions is absolutely disgusting and something needs to be done about it.

Reported
Oct 2024
Incident date
Jul 2024
Mileage
Not provided
Outcome flags
None reported
Open ODI 11620834 at NHTSA →
EngineOct 2024 · ODI 11618999Details +

- My 2018 Mazda CX 9 started stalling and jittering at idle and then eventually during slow driving. - Next day I got a check engine light, took to Mazda service center at the dealership I have been going to for last 6 years since I bought the car. - Service center diagnosed that there was a coolant leak through the cylinder head which seems to have cracked. - Further investigation indicated that this has been identified on many other similar Mazda engines and a Technical Service Bulletin had been issued by Mazda to Dealers. - On probing initially, dealership declined they were aware of any such problem. - The amount of repair for the engine replacement (cylinder head and other parts) is exuberant and is almost half of the value of my car, and is not expected for a low 44,000 miles car. - This had posed safety issue for my family since the stressed engine with leak in cylinder head could lead to fire and fatality. - I am awaiting response from Dealership and Mazda corporation case#[XXX] for a response especially when this issue has been filed under a class action lawsuit: [XXX] INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Reported
Oct 2024
Incident date
Sep 2024
Mileage
Not provided
Outcome flags
None reported
Open ODI 11618999 at NHTSA →
EngineOct 2024 · ODI 11617788Details +

Engine cylinder head is leaking coolant. This is a known issue by Mazda as they have submitted a TSB on the issue but have yet to submit a recall. The leak causes overheating along with pollution of coolant fluid into the environment. The problem was diagnosed by a Mazda dealership. The leaking occurred before a light came on the dashboard. The light on the dashboard only came on once the engine began overheating.

Reported
Oct 2024
Incident date
Sep 2024
Mileage
Not provided
Outcome flags
None reported
Open ODI 11617788 at NHTSA →
EngineSep 2024 · ODI 11616967Details +

Over heating /coolant leak

Reported
Sep 2024
Incident date
Sep 2024
Mileage
Not provided
Outcome flags
None reported
Open ODI 11616967 at NHTSA →
Power TrainSep 2024 · ODI 11615751Details +

coolant leaks at cylinder head , Mazda of America knows issues but not willing to recall , they hava a bulletin number 01-002/23 . pls help

Reported
Sep 2024
Incident date
Sep 2024
Mileage
Not provided
Outcome flags
None reported
Open ODI 11615751 at NHTSA →
EngineSep 2024 · ODI 11614956Details +

While driving on an interstate service drive in Michigan, my 2018 Mazda CX9 GT suddenly lost power and began flashing overheating warnings. I tried to move my vehicle to a safe spot while the warning and sudden loss of power was happening, which took a moment due to traffic flow and my family being in the car. I moved the car off the road, and let it cool. I slowly drove the car to a parts store to get coolant. Once the cooling system was filled, I brought the car home and began researching the problem. According to internet threads like Reddit this is a wide spread problem happening among Mazda vehicles with several law firms researching class action lawsuits. My car is stuck at the dealership until I can find $12,000 to fix it, and sadly there are hundreds more just like me according to sites like [XXX] and [XXX] [XXX] [XXX] [XXX] [XXX] [XXX] And includes a Mazda Service Bulletin which indicates that there are design faults in the original cylinder head that causes the issue and that repair techs should replace failed parts with the updated and redesigned cylinder head. [XXX] INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Reported
Sep 2024
Incident date
Aug 2024
Mileage
Not provided
Outcome flags
None reported
Open ODI 11614956 at NHTSA →
Unknown Or OtherAug 2024 · ODI 11611415Details +

Approximately three weeks ago, a message on my dashboard said to pull over immediately. Your car is overheating. I pulled over to a nearby auto shop, which indicated that I was just low on coolant. They topped off the coolant, and everything appeared fine. Two weeks later, I got the same message on the dashboard, saying my car was overheating to pull over immediately. I pulled into a nearby auto parts store and purchased coolant for the vehicle. When I checked the reservoir, it was bone dry. I added coolant and drove the car home. The following day, I checked the reservoir to see if there was still coolant, but it was all gone. I scheduled an appointment with the Mazda dealer to have the car inspected. I also checked the Mazda Forum website to see if other vehicles of my make and model had similar issues since I had never experienced this before. I found that the overheating in vehicles of my make and model was a "known issue" with Mazda. When I took it to the dealer the next day, the service agent informed me that the "known issue" was only with the Turbo model. I explained that my vehicle is a turbo model. He said that Mazda did not have to cover any costs because no recall was issued, even though it is a known issue. Mazda is now refusing to cover the repair and has indicated that the repair and replacement of the engine will cost approximately $9800. If I had been alerted earlier, I would have been able to have the car repaired.

Reported
Aug 2024
Incident date
Aug 2024
Mileage
Not provided
Outcome flags
None reported
Open ODI 11611415 at NHTSA →
EngineAug 2024 · ODI 11610568Details +

Vehicle had bucking coming to a stop. Noticed coolant was l9w, and temp guage was fluctuating at a stop slightly. Brought it to Lester Glenn mazda in toms river NJ, service writer informed us it is the cylinder head, and that the repair is approx $11,000. Vehicle only has 85000 miles on it, and was told by dealer that there is nothing they will do. This is a known issue, with a TSB issued in 2021 due to a defect in design where the turbo charger is mounted to the cylinder head. At this point, we are requesting the manufacturer take at least part of the responsibility of the poor design they sold to the open market, that is clearly a safety hazard to my wife and 4 kids, 1 of which is an infant.

Reported
Aug 2024
Incident date
Aug 2024
Mileage
Not provided
Outcome flags
None reported
Open ODI 11610568 at NHTSA →
Engine And Engine CoolingAug 2024 · ODI 11609734Details +

The contact owns a 2018 Mazda CX-9. The contact stated that while driving at various speeds, the engine started overheating within approximately 15 minutes of driving. The contact had to pull over and wait for a while to let the engine cool down before continuing to drive. The contact stated that there was a message that the engine was overheating and to stop driving the vehicle displayed. The vehicle was taken to the dealer where it was diagnosed that coolant was leaking into the cylinders due to a fracture in the cylinder head. The contact was unsure of the cylinders with the failure. The contact was informed that the engine needed to be replaced. The vehicle had not been repaired. The contact found a Technical Service Bulletin regarding the cylinder head failure. The manufacturer was made aware of the failure and confirmed that the VIN was not covered under the TSB and that the TSB had expired in 2023. The failure mileage was 76,000.

Reported
Aug 2024
Incident date
Jul 2024
Mileage
Not provided
Outcome flags
None reported
Open ODI 11609734 at NHTSA →
Power TrainAug 2024 · ODI 11609045Details +

Engine is leaking coolant apparently due to a cracked engine block caused by a manufacturing defect in the casting. Mazda has a Technical Service Bulletin, subject:Leaks at cylinder head and the number is 01-013/21. But they refuse to help cover their mistakes and now we owners are stuck with replacing an entire engine out of pocket. Shame on Mazda

Reported
Aug 2024
Incident date
Jul 2024
Mileage
Not provided
Outcome flags
None reported
Open ODI 11609045 at NHTSA →
EngineJul 2024 · ODI 11605395Details +

Mine Mazda 2018 CX9 had coolant leakage at 55K miles. Issue is with faulty cylinder head acknowledged by Mazda in below mentioned TSB. I open up a case with Mazda (File Number XXX). Dealer quoted 7500$ expense and Mazda is providing assistance of 3101$. I have always serviced at Mazda authorized dealership and this issue was never reported. TSB [XXX] INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Reported
Jul 2024
Incident date
Jun 2024
Mileage
Not provided
Outcome flags
None reported
Open ODI 11605395 at NHTSA →
Power TrainJul 2024 · ODI 11603552Details +

My car started leaking coolant from cylinder, it is known issue for these models, unfortunately Mazda cooperation doesn’t cover the expenses, there is Service Bulletin about it, so basically so many car got affected or will affect from this problem. It is manufacturer fault, not about customer usage or mistake.

Reported
Jul 2024
Incident date
Jun 2024
Mileage
Not provided
Outcome flags
None reported
Open ODI 11603552 at NHTSA →
EngineJun 2024 · ODI 11596193Details +

"High coolant temperature warning. Stop car at a safe place immediately " came up. Stopped car at a mechanic and diagnosed as coolant leak onto the engine.

Reported
Jun 2024
Incident date
Jun 2024
Mileage
Not provided
Outcome flags
None reported
Open ODI 11596193 at NHTSA →
EngineJun 2024 · ODI 11595029Details +

Due to the flawed engine design which is well documented for these engines, ours started leaking coolant and it was eventually discovered that the head had cracked, and we were forced to have the head replaced. This repair cost us approximately $7600. Our hope is that Mazda will eventually issue a recall.

Reported
Jun 2024
Incident date
May 2024
Mileage
Not provided
Outcome flags
None reported
Open ODI 11595029 at NHTSA →
Power TrainJun 2024 · ODI 11594397Details +

My vehicle had a coolant leak st the cylinder head around the exhaust manifold. The problem was confirmed by an independent service. No warning lamps, message or other symptoms of the problem prior to the failure did not appear. The problem was detected because coolant was dropping from the powertrain to the floor. When tha catalyst was removed it was found broken due to the high temperature but the car never display a high temperature warning lamp and the temperature display remains in normal position. The car could get on fire since no warnings or signal of high temperature was registered. After the situation occurred, I found a Technical Service Bulletin (No 01-01321) from Mazda North American Operations regarding this issue but since the problem occurred after the powertrain warranty the dealer did not accept to repair it. The probability that my car could get in fire was high since no warning lamps were display.

Reported
Jun 2024
Incident date
Feb 2024
Mileage
Not provided
Outcome flags
None reported
Open ODI 11594397 at NHTSA →
Unknown Or OtherJun 2024 · ODI 11592673Details +

The infotainment screen has spider like frost inside the screen. I've checked and other models have had this same issue and have been recalled and repaired. My model year 2018 is suffering the same issue and MAZDA has lagged on this problem. Please put out a recall on this as it is a hazard when you rely on your navigation system and other components the screen assists with.

Reported
Jun 2024
Incident date
Nov 2023
Mileage
Not provided
Outcome flags
None reported
Open ODI 11592673 at NHTSA →
EngineMay 2024 · ODI 11589675Details +

2018 CX9 with 74k miles. Took it back to the dealer where I bought it from and have an extended warranty. They are telling me the extended warranty denied the coverage for Coolant leak, engine replacement

Reported
May 2024
Incident date
Apr 2024
Mileage
Not provided
Outcome flags
None reported
Open ODI 11589675 at NHTSA →
EngineApr 2024 · ODI 11586004Details +

Cylinder head cracked at 100k. There is tsb knowing that this is a problem. It even stats that it happens during Manufacturing there was a defect. Coolant is leaking out the back side of the motor. Causing a over heating conditions stranding my family on the side of the highway.

Reported
Apr 2024
Incident date
Apr 2024
Mileage
Not provided
Outcome flags
None reported
Open ODI 11586004 at NHTSA →
EngineApr 2024 · ODI 11585527Details +

The 2018 Mazda CX-9 has been experiencing significant engine coolant leaks, which are suspected to stem from a manufacturing defect. The coolant leaks appear to be primarily caused by a casting defect in the engine block or cylinder head, exacerbated by the pressure and heat from the attached turbocharger. These defects lead to coolant escaping from areas that are typically obscured behind the exhaust manifold and turbocharger, making early detection difficult without detailed inspection.

Reported
Apr 2024
Incident date
Apr 2024
Mileage
Not provided
Outcome flags
None reported
Open ODI 11585527 at NHTSA →
SuspensionApr 2024 · ODI 11583243Details +

While I have not been involved in an accident yet, I have discovered an issue that is believed to be the same issue that other models are covered under a recall, yet for some reason my VIN is not included. The bulleting reference number is 02-001/20 that covers MAZDA 2016-2020 CX-9 models. I have a 2018 CX-9 touring that is exhibiting the exact action of the recall which is "creaking noise from front lower arm bushing/clunking noise from front shock absorber coil spring when driving over bumps". It is only getting worse as time goes on. I am confused as to why some vehicles would be included in this recall yet my year model is experiencing the same issues but is not covered under the recall. I don't know if people are not reporting it, which is why I am filling out this report today.

Reported
Apr 2024
Incident date
Jul 2023
Mileage
Not provided
Outcome flags
None reported
Open ODI 11583243 at NHTSA →
EngineApr 2024 · ODI 11583106Details +

Car started leaking coolant, and running rough / stalling. Eventually overheated due to lack of coolant. Mazda dealer reports Cylinder Head crack as the root cause of the issue. Car has 106K miles - and seems to have the same problem as referenced in NHTSA 10232269 [XXX] ) Mazda has decided to decline to offer any financial assistance in the repair. Replacement cost for just the cylinder head (not a complete engine) was quoted by a Mazda dealership to be $6800 - $7200. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Reported
Apr 2024
Incident date
Apr 2024
Mileage
Not provided
Outcome flags
None reported
Open ODI 11583106 at NHTSA →
EngineMar 2024 · ODI 11576133Details +

Engine coolant leaks at cylinder heads I started noticing the problem at around 50000 miles its a small coolant leak but car is almost 6 years old and now 54000 miles

Reported
Mar 2024
Incident date
Aug 2023
Mileage
Not provided
Outcome flags
None reported
Open ODI 11576133 at NHTSA →
EngineJan 2024 · ODI 11568859Details +

I recently bought a Mazda CX-9 and noticed that my vehicle was slightly overheating. The coolant level was very low. I took it back to the dealership I bought it from and they confirmed that there was a crack in the cylinder head and are working on the repair. After further research, I am seeing this is common with these models. Mazda is aware but not taking responsibility.

Reported
Jan 2024
Incident date
Jan 2024
Mileage
Not provided
Outcome flags
None reported
Open ODI 11568859 at NHTSA →
EngineJan 2024 · ODI 11566536Details +

Cracked Cylinder Head Verified by Mazda Dealer . Noted it seems to be a very common problem with Mazda cx9 2018 models and has Multiple TSB on issue so I kept very close eye on car and took it in as soon as I smelled burning smell suggesting a leak , before the car had the chance to overheat and put myself and kids in danger. My car is under 40k miles for a 2018 with consistent maintenance - this is known problem since 2021 and needs to result in a recall.

Reported
Jan 2024
Incident date
Jan 2024
Mileage
Not provided
Outcome flags
None reported
Open ODI 11566536 at NHTSA →
EngineJan 2024 · ODI 11566091Details +

Mazda has a known technical service bulletin [XXX] which has numerous engine cylinder heads which leaks coolant causing the engine to overheat without warning. On new cars. Mazda knows it’s an issue and has not pushed this information down to its consumers. [XXX] INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Reported
Jan 2024
Incident date
Jan 2024
Mileage
Not provided
Outcome flags
None reported
Open ODI 11566091 at NHTSA →
Unknown Or OtherJan 2024 · ODI 11564928Details +

Cracked cylinder head which lead to coolant leak.

Reported
Jan 2024
Incident date
Aug 2023
Mileage
Not provided
Outcome flags
None reported
Open ODI 11564928 at NHTSA →
EngineDec 2023 · ODI 11561290Details +

Engine coolant leaking due to cracked cylinder head, found by Mazda dealership service inspection and diagnostics. Powertrain warranty only covers this until 80,000 miles, our vehicle is 116,000.

Reported
Dec 2023
Incident date
Dec 2023
Mileage
Not provided
Outcome flags
None reported
Open ODI 11561290 at NHTSA →

This page shows the latest 50 reports to keep it usable. The count above includes every complaint NHTSA has returned for this model year.

Recalls(2)

Open a recall to read what NHTSA says is wrong, what can happen, and how it gets fixed. Check the VIN and remedy eligibility with a dealer; federal no-charge requirements have an age limit, though a manufacturer may offer more coverage.

Fuel SystemDec 2021 · 21V875000Details +

Mazda North American Operations (Mazda) is recalling certain 2018 Mazda3, Mazda6, 2019 CX-3, 2018-2019 MX-5, CX-5, CX-9, and 2019-2020 Mazda2 vehicles. The impeller inside the low-pressure fuel pump may crack and deform, potentially causing the fuel pump to fail.

Risk: Fuel pump failure may cause an engine stall, increasing the risk of a crash.

Remedy: Dealers will replace the fuel pumps, free of charge. Owner notification letters were mailed July 18, 2022. Owners may contact Mazda customer service at 1-800-222-5500 Option 4. Mazda's number for this recall is 5321K.

Open full NHTSA recall record →
Electrical System · 19V403000Details +

Mazda North American Operations (Mazda) is recalling certain 2018 CX-9 vehicles. The wiring harness may disrupt electrical communications and disable the passenger frontal air bag, turn signals, and/or engine starting system.

Risk: The passenger frontal air bag may not deploy, increasing the risk of injury. Inoperable turn signals prevent the driver from signaling to other drivers, increasing the risk of crash.

Remedy: Mazda will notify owners, and dealers will repair the wiring harnesses, free of charge. The recall began July 26, 2019. Owners may contact Mazda customer service at 1-800-222-5500, Option 4. Mazda's number for this recall is 3419E.

Open full NHTSA recall record →

A campaign can apply to this model year without being incomplete on a specific vehicle. Check the VIN with NHTSA or a dealer to confirm whether a particular car needs repair.

Investigations

0 NHTSA investigations on record

No investigations are on record as of Jul 2026. An empty record is not a clean bill of health.

Crash-test ratings

2018 Mazda CX-9 SUV AWD NHTSA source

Overall
Frontal
Side
Rollover

2018 Mazda CX-9 SUV FWD NHTSA source

Overall
Frontal
Side
Rollover

Source: NHTSA New Car Assessment Program (NCAP).

Fuel economy by trim

TrimEngineDrivetrainCityHwyCombined
CX-9 2WD2.5L 4-cylFront-Wheel Drive222824
CX-9 4WD2.5L 4-cyl4-Wheel Drive202623

EPA laboratory estimates by trim and engine. Actual mileage varies with driving, weather, load, and maintenance. EPA source.

Before you buy

Useful next checks

Federal records tell you about patterns. These checks can tell you more about the specific car in front of you.

These are affiliate links. TireKick may earn a fee if you use one.

Compare the year-by-year record

Open another year for its own evidence-gated decision. TireKick does not crown a best year from raw complaint totals.

2018 Mazda CX-9: frequently asked

What does the complaint record show for the 2018 Mazda CX-9?

Owners filed 125 NHTSA complaints about the 2018 Mazda CX-9. This is raw owner-reported complaint volume with no production or exposure normalization, so it is not a reliability score or a best/worst-year ranking.

What are the most common problems on the 2018 Mazda CX-9?

The most-reported problem areas are Engine (48% of complaints) and unknown or other (14%).

How many recalls does the 2018 Mazda CX-9 have?

2 recalls have been issued that affect the 2018 Mazda CX-9, covering components such as fuel system. Check the VIN with NHTSA and ask a dealer to confirm remedy eligibility; federal no-charge requirements have an age limit, though manufacturers may offer more coverage.

What gas mileage does the 2018 Mazda CX-9 get?

The EPA rates the 2018 Mazda CX-9 between 23 and 24 mpg combined, depending on trim and drivetrain.