2018 Mazda CX-9 Engine cooling Problems
- Complaints
- 2about this part
- Share
- 2%of 128 total for the year
- Median mileage
- 82,040miles
- Trend
- Not enough dataFewer than 15 complaints, too few for a reliable trend.
NHTSA recorded 2 complaints about the engine cooling of the 2018 Mazda CX-9, 2% of the 128 complaints for this model year. Where a mileage was given, the median is 82,040 miles.
Fewer than 15 complaints name this part, so treat the figures as a rough indication only.
Example complaints
Selected from NHTSA records; personal details are removed. They are consumer reports, not findings.
“The contact owns a 2018 Mazda CX-9. The contact stated that while the vehicle was parked, he noticed an abnormal odor inside the vehicle. Upon inspecting the vehicle, the contact found a trail of coolant. The vehicle was taken to an independent mechanic, who confirmed that coolant was leaking, and referred the contact to the dealer for a diagnostic test. The vehicle was not repaired. The manufacturer was not made aware of the failure. The failure mileage was approximately 88,080.”
NHTSA complaint #11540793, filed 2023-08, 88,080 miles“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. …”
NHTSA complaint #11609734, filed 2024-08, 76,000 milesRelated service bulletins
- 10251387Feb 12, 2024Mazda has developed factory recommended scheduled maintenance services that support all major vehicle systems. Mazda recommends dealers follow the scheduled maintenance tables as…
- 10248392Dec 5, 2023There is a concern that some water pumps are being replaced that are not faulty, due to signs of a very small coolant leak from the bleed hole. This Service Alert is to inform…
- 10244679Oct 11, 2023If you encounter any type of electrical concern (e.g, dead battery, engine no start, DTC(s) stored...), interview the customer before proceeding with normal MGSS diagnosis by…
- 10238663Jun 5, 2023Some vehicles may exhibit oil leakage from the drive belt auto tensioner and rattling noises from the engine compartment. This may be caused by insufficient sealing at the drive…
- 10238695Jun 1, 2023Some customers may complain of a lack of power under heavy load without any warning lights or DTCs. This concern may be due to a loose or detached hood weatherstrip, which can…
- 10237216May 24, 2023If you encounter any type of electrical concern (e.g, dead battery, engine no start, DTC(s) stored...), interview the customer before proceeding with normal MGSS diagnosis by…
- 10232269Feb 10, 2023Some vehicles may have coolant leaks at the cylinder head around the exhaust manifold (as shown below). There may be cracks at the stud bolt hole (1) or at the outside of the…
- 10232266Feb 3, 2023Some customers may complain about a poor acceleration and rough idling or the CHECK ENGINE light ON with DTC P0301:00, P0302:00, P0303:00, P0304:00.NOTE: Only turbo engines are…
- 10230865Jan 23, 2023When servicing SKYACTIV engine vehicles requiring to replace the Oil Galley Plug and Crush Washer, order the required part numbers below. These parts are not listed in GEPC and…
- 10230890Jan 19, 2023Some vehicles may have coolant leaks at the cylinder head around the exhaust manifold (as shown below). There may be cracks at the stud bolt hole or at the outside of the exhaust…
Engine cooling: other model years
Other parts of the 2018 Mazda CX-9
76 complaintsOther or unknown
20 complaintsElectrical system
15 complaintsTransmission and drivetrain
13 complaintsBrakes
11 complaintsFuel system
7 complaintsForward collision avoidance
4 complaintsBack-over prevention (rear camera)
3 complaintsSteering
3 complaintsVisibility (wipers, defrost, mirrors)
3 complaintsAir bags
2 complaintsSeats
2 complaints
← All problems reported for the 2018 Mazda CX-9
About this data. Data from NHTSA (ODI) complaints, recalls, TSBs and investigations, updated Oct 27, 2026. Complaints are unverified consumer reports and may be duplicated or inaccurate.
To check a specific vehicle for open recalls, use its VIN at nhtsa.gov/recalls. Methodology