2021 Mazda CX-9 engine problems
This is a safety-related system. If you notice symptoms, stop driving and have it inspected.
What owners report
“2021 Mazda CX-9 (VIN: JM3TCBDY3M0538768 / 72,400 mi) Vehicle has suffered complete, sudden loss of motive power at high freeway speeds on four separate occasions. Without warning, the engine loses all propulsion, essentially stalling mid-traffic and forcing me to dangerously coast across active freeway lanes to the shoulder. This creates an extreme risk of a high-speed rear-end collision. No crash or injuries have occurred yet, but the car is entirely unsafe to drive. The authorized Mazda dealer…”
NHTSA complaint · filed 10/14/2026
“The vehicle was parked stationary in the driveway with the engine running for 3-5 minutes with the A/C on. The vehicle then accelerated forward into my garage causing damage. Once I entered the vehicle, both the dash and shifter displayed park. Current TCU system internal failures have been reported from the pulling of data from Mazda.”
NHTSA complaint · filed 08/10/2026 · crash
“1) What component or system failed or malfunctioned: On 6/12/2026 While drive on the highway with our daughter in the car and we experienced a high speed stall. The engine failed and we lost power. We barely got the car of the highway and coasted into a parking lot. 2) Life threating for Father, Mother and daughter and other drivers on the highway. 3) The Mazda dealer stated they were unable to reproduced problem. The diagnostic report showed few random misfired on two cylinders 2 & 3. …”
NHTSA complaint · filed 07/23/2026
“This complaint refers to Mazda and it's dealer refusal to properly execute the warranty work under the SSPD5 Valve Stem Seal Class Action Campaign and does not follow the Court's approval of the final Settlement Agreement. I assert that Mazda and it's dealer are not following the SSPD5 repair procedures. 1. I have documentation and complaints going back to Dec-2023 with this particular dealer that I have experienced low level oil consumption within the 7,500 mile oil change interval. The dealer …”
NHTSA complaint · filed 07/12/2026
“Check engine light comes on and error P0303 comes on. Had an independent mechanic do the following and after each one, error P0303 still came on 1. Swap the ignition coils from 2 to 3 2. Swap spark plugs from 2 to 3 3. Swapped injectors 4. Compression test 5. Leak down test 6. Changed the spark plug, coil and injectors 7. Looked for vacuum leaks. Mechanic believes that it is related to the cracked cylinder head in the recall, MC-10232269-0001.pdf. My vehicle is just outside of the recall range …”
NHTSA complaint · filed 06/18/2026
“The contact owns a 2021 Mazda CX-9. The contact stated that while accelerating quickly and entering the highway, there was no motive power to the vehicle. While crossing the highway in the right lane, driving at 65 MPH, the vehicle in front moved over; there was a parked vehicle. The contact was able to stop the vehicle before causing a crash. The driver was starting to accelerate, but there was no motive power when the accelerator pedal was depressed. The smart brake system malfunction message …”
NHTSA complaint · filed 08/14/2024
“Consumes over 2 quarts of oil between recommended oil changes. The dealer made excuses about needing to use a different oil but it has not improved the problem. The warning light for low oil went off after less than 3000 miles. It was 2 quarts down.”
NHTSA complaint · filed 06/20/2024
“I just purchased this vehicle 2 months ago. Yesterday my oil light came on, I pulled over and checked the oil it was completely low. I had to put a quart of oil in it. After that I did some research and learned this seems to be an issue with some 2021 models the cx9 included. There needs to be a recall on this and Mazda needs to fix this issue. These cars cost way to much to have to put a quart of oil every month.”
NHTSA complaint · filed 01/02/2024
Unverified owner reports from NHTSA's public complaint database.
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- How common are 2021 Mazda CX-9 engine problems?
- 21 owners reported engine issues to NHTSA for the 2021 Mazda CX-9, 1 involving a crash. Counts scale with how many were sold.
- Is there a recall for 2021 Mazda CX-9 engine problems?
- No matching recall is on file. Check your VIN at nhtsa.gov/recalls for the latest.