Mazda CX-9 Common Problems

ENGINE

Owners report frequent issues with the 2018 Mazda CX-9 involving cracked cylinder heads, leading to coolant leaks and engine overheating. Symptoms commonly described include sudden engine overheating warnings, loss of power, and visible leaks or smoke, often resulting in the vehicle becoming undriveable. These problems are typically noted around 55,000 to 130,000 miles, with some owners mentioning technical service bulletins and extended warranties that address the issue. Safety implications include the potential for sudden loss of engine power while driving, though no crashes or injuries are reported. Buyers should be aware of these recurring engine issues and the associated repair costs, as well as the potential for vehicles to be outside warranty coverage.

ENGINE

Owners report that the 2021 Mazda CX-9 frequently experiences excessive oil consumption, with many noting the need to add approximately one quart of oil every 2,500 to 3,500 miles. Complaints often mention the low oil warning light activating and the discovery of low oil levels upon inspection. Some owners attribute the issue to defective valve stem seals, as referenced in technical service bulletins and a class action lawsuit. The majority of these issues are reported around 10,000 to 50,000 miles. While no direct safety incidents such as crashes or fires are described, the potential for engine damage or failure due to oil loss is a concern for owners. This information is particularly relevant for used car buyers considering this model.

UNKNOWN OR OTHER

Owners report recurring issues with the infotainment screen on the 2018 Mazda CX-9, frequently describing spider-like cracks or frost inside the screen, which can obscure navigation and backup camera displays. These symptoms often appear after a few years of ownership, with some complaints noting the problem at around 23,000 miles. Additionally, there are reports of sudden unintended acceleration while braking, with at least one incident leading to a crash. Some owners also mention overheating issues linked to coolant leaks, particularly in turbo models, resulting in significant repair costs. These issues highlight potential safety concerns, including impaired visibility and loss of vehicle control.

Severity signals: 1 crash, 0 fire, 0 injury reports

ENGINE

Owners of the 2019 Mazda CX-9 frequently report issues related to engine overheating and coolant leaks, often attributed to cracked cylinder heads. Common symptoms include dashboard warnings for high engine temperature, noticeable coolant leaks, overheating, and the presence of smoke or burning odors. These issues typically arise between 25,000 and 124,000 miles. Safety concerns are evident, with reports of sudden loss of engine power, engine shutdowns while driving, and potential fire risks from coolant leaks onto hot engine components. Buyers should be aware that multiple complaints reference a Mazda Technical Service Bulletin acknowledging these defects, and engine replacement is often cited as the necessary remedy.

ELECTRICAL SYSTEM

Owners of the 2018 Mazda CX-9 frequently report issues with the vehicle's infotainment system, particularly "spider cracking" on the screen, which obstructs visibility of critical functions such as navigation and backup cameras. These complaints often note the problem emerging around two years after purchase and worsening over time. Another common issue involves the vehicle's electrical system causing unexpected braking, as indicated by a "Smart System Brake Malfunction" warning, posing a risk of sudden loss of control. Additionally, some owners describe battery drainage linked to the liftgate and seat heater malfunctions, with one instance resulting in a fire. These patterns suggest potential safety implications, including the risk of rear-end collisions and vehicle fires.

Severity signals: 0 crash, 1 fire, 0 injury reports

POWER TRAIN

Owners report frequent issues with coolant leaks in the 2018 Mazda CX-9, often attributed to cracked cylinder heads. Complaints frequently mention symptoms like coolant loss, lack of warning lights, and overheating, with some cases leading to engine damage. These issues are typically reported around 53,000 to 102,000 miles. Safety implications include potential engine failure at highway speeds, with some owners expressing concern over the risk of fire due to undetected high temperatures. Buyers considering this model should be aware of these documented issues and the potential repair costs involved.

UNKNOWN OR OTHER

Owners of the 2019 Mazda CX-9 frequently report issues with internal spider cracks on the infotainment center display, which can affect visibility and functionality of features like the backup camera and GPS. These cracks are reported as internal and not physically detectable by touch. Complaints often reference Mazda's existing service alerts for earlier models, suggesting a known issue that has not been addressed for the 2019 model year. Additionally, one owner reports ongoing issues with the Mazda Smart Braking System, where warning lights activate erroneously, impacting the use of cruise control. Although no crashes or fires are reported, the visibility issues with the display and the braking system's malfunction could pose safety risks.

ELECTRICAL SYSTEM

Owners report issues with the 2019 Mazda CX-9's electrical system, primarily involving the infotainment screen and windshield wipers. Complaints frequently mention the infotainment screen developing spider cracks, making it difficult to use, with some owners noting this issue around 45,000 miles. Windshield wipers are reported to activate independently and fail to turn off, particularly after replacing the windshield with non-OEM parts. Additionally, one report describes a fire originating from the rear passenger side, while another details multiple battery replacements due to starting issues linked to the power liftgate module. Safety implications include a report of electrical system failures affecting emergency braking and lane assist features, leading to a loss of control.