2018 Mazda CX-9 problems & reliability
125 owner complaints filed with NHTSA for the 2018 Mazda CX-9, alongside 2 safety recall campaigns. Last verified Aug 7, 2026. Complaints are unverified reports submitted by owners to the federal Office of Defects Investigation.
Each complaint is counted once (by NHTSA case number), even when it names several vehicles.
2 complaints report injuries (2 injured).
Federal crash records (FARS 2020–2023): 2018 Mazda CX-9 vehicles were involved in 11 fatal crashes with 6 occupant deaths. Involvement counts are not adjusted for how many are on the road and do not imply fault or a vehicle defect.
Most reported problems
| Component | Complaints | Share |
|---|---|---|
| Engine | 73 | 58% |
| Unknown OR Other | 19 | 15% |
| Electrical System | 15 | 12% |
| Power Train | 13 | 10% |
| Service Brakes | 11 | 9% |
| Fuel/propulsion System | 5 | 4% |
| Forward Collision Avoidance | 4 | 3% |
| Back Over Prevention | 3 | 2% |
| Steering | 3 | 2% |
| Visibility/wiper | 3 | 2% |
Component groups as classified by NHTSA. A complaint can name more than one component, so shares may sum to more than 100%.
Common symptoms owners describe
Keyword analysis of complaint narratives; one complaint can describe several symptoms.
Complaints by incident year
What owners report
“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…”
Engine · filed Jul 15, 2026
“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…”
Seats · filed Jun 8, 2026
“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…”
Engine · filed Jun 5, 2026
Verbatim excerpts from complaints filed with NHTSA. Reports are not independently verified.
Technical service bulletins
469 manufacturer communications (TSBs, service campaigns, warranty extensions) are on file with NHTSA for the 2018 Mazda CX-9. The 10 most recent:
This SA supersedes the previously issued SA(s) listed below. The changes are noted in Red. SA-061/25 12/17/25 DESCRIPTION If you encounter any type of electrical concern (e.g, dead battery, engine no start, DTC(s)…
SA-041-26 · Service Bulletin/Repair Instructions · issued Jun 19, 2026
This bulletin supersedes the previously issued bulletin(s) listed below. The changes are noted in Red. 01-008/23 06/05/23 Some vehicles may exhibit rattling noises from the engine compartment and oil leakage from the…
01-008-26 · Service Bulletin/Repair Instructions · issued May 1, 2026
DESCRIPTION Some vehicles may require the replacement of a damaged VIN plate or vehicle certification label. To obtain a replacement VIN plate (bulkhead-mounted and visible through the lower-left area of the…
SA-031-26 · Service Bulletin/Repair Instructions · issued Apr 30, 2026
This Service Alert supersedes the previously issued SA listed below: The changes are noted in Red. SA-011/24 02/12/24, 06/06/24, 07/29/24 DESCRIPTION Mazda has developed factory recommended scheduled maintenance…
SA-029-26 · Service Bulletin/Repair Instructions · issued Apr 21, 2026
This Service Alert supersedes the previously issued M-Tip(s) listed below. The changes are noted in Red text. MT-002/19 09/30/19 and 12/19/19 DESCRIPTION If an engine assembly is replaced after a catastrophic internal…
SA-026-26 · Service Bulletin/Repair Instructions · issued Apr 16, 2026
This Service Alert supersedes the previously issued SA(s) and TSB(s) listed below: The changes are noted in Red. SA-035/24 05/31/24 DESCRIPTION There is a concern that some water pumps are being replaced that are not…
SA-014-26 · Service Bulletin/Repair Instructions · issued Mar 11, 2026
There are currently 2 methods for cutting a new auxiliary key blank. A. Auxiliary Key Trace Cut Method • B. Auxiliary Key Code Cut Method 2019 and newer models require a 10-digit key code to accurately cut keys •…
SA-005-26 · Service Bulletin/Repair Instructions · issued Jan 26, 2026
Some customers may report an odor or water in the HVAC system and upon inspection, the cabin air filter may be found to be wet.
SA-001-26 · Service Bulletin/Repair Instructions · issued Jan 5, 2026
If 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 asking if any aftermarket devices have been…
SA-061-25 · Service Bulletin/Repair Instructions · issued Dec 17, 2025
A musty/mildew type odor may come from the vents when the air conditioning (A/C) system is operating. It is most noticeable when the A/C is first turned ON. This odor is the result of mold growth in the A/C…
07-004-25a · Service Bulletin/Repair Instructions · issued Dec 10, 2025
TSBs are repair guidance manufacturers send to dealers — they are not recalls and repairs are not automatically free. Full documents are available on NHTSA’s site.
Safety recalls
The 2018 Mazda CX-9 has 2 NHTSA recall campaigns — recall repairs are free at franchised dealers regardless of the vehicle’s age.
Check whether your specific vehicle is affected
Recall campaigns often cover only certain VIN ranges. Enter your VIN on the official NHTSA site to confirm whether your vehicle is included and whether the repair is still open.
Check VIN on NHTSA →Buying a used 2018 Mazda CX-9?
- · Decode the seller’s VIN with our free VIN decoder to confirm the exact year, engine and trim.
- · Check for unrepaired recalls by VIN on NHTSA’s official lookup — recall repairs are free.