Most common 2018 Mazda CX-9 problems
Share of the 128 complaints; one complaint can involve more than one system. "~" is the median mileage when the problem started.
Mazda CX-9 complaints by model year
Best CX-9 years: 2015, 2022, 2020. Years to avoid: 2012, 2011, 2018, 2008, 2010. Compare all years →
2018 Mazda CX-9 recalls (2)
Fuel system, gasoline › Delivery › Fuel pump
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.
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.
Electrical system › Wiring
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.
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.
What 2018 Mazda CX-9 owners say
Engine & cooling all 78 →
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 contact owns a 2018 Mazda CX-9. The contact stated that while the vehicle was parked, he observed condensation under the vehicle. The vehicle was towed to an independent mechanic where it was diagnosed that the engine needed to be replaced. The vehicle was repaired but the failure persisted. The contact stated that while the vehicle was parked, he observed condensation under the engine compartment and on the top of the engine. The vehicle was taken to an independent mechanic where it was diagnosed that there was a crack in the cylinder head and that the engine needed to be replaced. The vehicle was not repaired. The manufacturer was notified of the failure. The failure mileage was 68,000.
Electrical system
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.
The main infotainment display randomly exhibited "spider cracking" which obstructs the view of the material being displayed within the screen. It is unsafe because the operator is unable to see maps, time, locations, controls, reverse cameras, etc. All of these are displayed in the screen and, due to the manufacturing defect, the operator is distracted by straining to see what is displayed behind the cracking. This is a well documented issue plaguing Mazda vehicles. Mazda has admitted it as defective, and are fixing the problem in the 2016-17 models. However, the 2018 model (which has the same screen as the 2016-17) is being refused. The fix needs to be extended to the 2018 model and beyond since it iw clear this it is still a widespread issue. …
Transmission & drivetrain
I own a 2018 Mazda CX - 9 with only 53,300 miles. I noticed something was wrong with my engine and had no idea what the issue was. My car would not shut off immediately when I turned it off and the fan was on super high speed. The day before my appointment with my mechanic, the engine light turned on. I was stuck in a parking lot and a friend suggested I use his car to go buy coolant just in case it was needed. Sure enough, I was completely out of coolant. When my mechanic inspected the car he told me I had a coolant leak and suggested I take it to the dealer as they would know immediately what the problem was. …
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. …
2018 Mazda CX-9 engines & fuel economy
| Engine | Transmission | Drive | MPG city / hwy / combined |
|---|---|---|---|
| 2.5L 4-cyl turbo | 6-speed automatic | FWD | 22 / 28 / 24 |
| 2.5L 4-cyl turbo | 6-speed automatic | 4WD | 20 / 26 / 23 |
EPA ratings. Class: Small SUV.
Frequently asked questions
Is the 2018 Mazda CX-9 a good car?
Based on 128 owner complaints filed with NHTSA, the 2018 CX-9 rates avoid: 2.2× as many complaints as a typical year of the CX-9 at the same age. It is one of the CX-9 years we suggest avoiding. Complaint counts don't account for sales volume or individual maintenance, so have any used car inspected before buying.
What is the most common problem with the 2018 Mazda CX-9?
The engine & cooling — 78 complaints, 61% of all complaints for this model year. Next are the electrical system (15) and transmission & drivetrain (13).
How many recalls does the 2018 Mazda CX-9 have?
There are 2 recalls for the 2018 Mazda CX-9, the most recent from November 12, 2021 (fuel pump). Recall repairs are free at any authorized dealer — check whether yours has been done with the VIN recall check.
What are the best and worst years of the Mazda CX-9?
The best years by complaints, compared at the same age, are 2015, 2022 and 2020. Years to avoid or approach with caution: 2012, 2011, 2018, 2008 and 2010. See the full Mazda CX-9 years comparison.
At what mileage do 2018 Mazda CX-9 problems happen?
The median mileage reported in complaints is about 28,000 miles; 69% of problems with a recorded mileage started before 50,000 miles.
Source: U.S. National Highway Traffic Safety Administration (NHTSA) — owner complaints through October 20, 2026, recalls and defect investigations; fuel economy from the EPA. Complaints are unverified reports and are not proof of a defect. How we rate model years.