2021 Mazda CX-9 Problems

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.

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. Autozone detected codes P0300 with Secondary DTCs U0442-00 4) There car was only inspected by the dealer. The vehicle has not been inspected by Mazda the manufacturer. We requested Mazda to escalate this to the District Service Manger and to open hotline call with Mazda corporate but both of these were denied. All our service has been performed at Mazda dealer, including oil changes. We have always received a video of them working on our car with a detailed summary of what done. We did not receive the video or diagnostic report for this issue. 5) There were no warning lamps, no messages or other symptoms of the problem prior to the failure.

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.

Backup camera shows three to four feet before red collision line is not accurate causing severe damage to my garage door.

Hello, I have been to a Mazda dealer complaining of clicking and squeaky brakes for 2 years now. Dealer replaced both front and back breaks and rotors around 22k year ago and to my surprise the issues persist, currently vehicle is at 49k. There is a TSB( 04-001/22) out for my vin and year, so they know its a manufacturing defect and all they do is throw white break grease and a month later the noise is there again when breaking , backing up. I am not the only one, people of reddit confirm this and so does a general google search. Besides that i love the car and the dealer was super cool about it all but I'm sorry, this is unacceptable, Every time i go get an oil change i ask about a fix and nothing.

6/29/2023--Vehicle stopped suddenly with i-ACTIVESENSE system malfunction, Dynamic Stability Control malfunction, Engine malfunction, engine output reduced, Front radar sensor malfunction. Dealer said these faults due to bad battery--replaced battery per Service Manager [XXX] at Lakeland Mazda. 9/10/2023--Incident #2 with same faults as above with vehicle stopping suddenly at risk of creating a rear end collision. Lakeland Service Manager [XXX] now said that the faults are due to a faulty ERG valve. Lakeland Mazda and [XXX] are absolutely clueless as to the root cause of this problem and are releasing the vehicle back to the customer with the potential of causing a significant collision that can result in serious injury and/or death. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

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.

My vehicle is part of Mazda's 2021-2022 Mazda Valve Stem Seal Settlement. The dealership had yet to call me in for the repair of said valve seal repair as I was on a list. The settlement is suppose to extend out the powertrain warranty on the vehicle 2 years/24,000 to 7 years/84,000. My vehicle has 60,083 miles on it. One of the cylinders on my vehicle lost compression. The dealership and Mazda both say they will not cover the cost for repair as they only are covering things in the powertrain relate to oil consumption. The cylinders are part of the powertrain and carbon buildup from excessive oil burning because of the defective seal causes valve damage or sticking which will cause compression loss. Mazda is actively denying what they agreed to in the settlement and costing people money for repairs that should be covered.

2021 Mazda CX-9 Frontal collision at a speed between 10-20 mph. Car shut down after collision and was not drivable. Concern is the driver side airbag did not deploy. (Neither did passenger but there was no person in the passenger seat)

REAR PASSENGER HANDLE AND HOOK ABOVE SEAT IN ROOF SPLINTERED INTO SHARP PROJECTILES FLYING THROUGH CABIN WHEN AIR BAG DEPLOPYED I SHOWED THE SHARP PIECES TO MY INSURANCE ADJUSTER THE POWER OF THE RIGHT CURTAIN AIR BAG DEPLOYMENT BROKE THE HANDLE TO PIECES AND IF ANYONE HAD BEEN IN THE BACK SEAT THEY COULD HAVE HAD AN EYE PUT OUT OR BEEN EMPLAILED BY THE SHARP PIECES

On 4/30/2022 the rear door lift gate opened unexpectedly and hit the ceiling of a parking garage (The Summit at Las Calinas, Irving Texas) , the glass window shattered, glass fell in and outside the car. An unfamiliar beeping was heard before the accident, but the source could not be located prior to the impact with the ceiling. A lift gate ajar warning indicator light likely flashed on the dash but was not noticed. We surmised that the root cause was likely due to unintentional pressing of the rear lift gate key fob button (driver had put key fob in pants pocket). This unintentional and unexpected opening of the lift gate has happened on at least 4 prior occasions when the key fob lift gate button has been unintentional pressed. One time resulting in being hit in the head with the lift gate! Potential Risks: 1) People near the rear of the car can be struck when the lift gate unexpectedly opens, 2) Young children who are sitting in the third seat are exposed, 3) Trunk contents can spill out if not secured, 4) Valuables are exposed if lift gate opens while parked unbeknownst to the driver, 5) Damage to vehicle if rear lift gate opens in a home garage and hits the garage door, 6) other Mazda owners as reported on Reddit.(https://www.reddit.com/r/MazdaCX9/comments/mf3h5w/back_trunk_opening_by_itself/) Problem was reported to TOWN NORTH MAZDA dealer. Insurance claim not filed because cost of window replacement is below deductible. We were grateful that no one was hurt and that the car could be driven home.

The oil light keeps coming on before your initial oil change. Also, the oil is actually low. They have already changed it and I'm having the same problem in less than 2 months.

I was driving approximately 75-80 mph (speed limit for I-90 is 80 mph) on I-90 Eastbound in South Dakota (approximately 5-8 miles from Sioux Falls, SD) in the left-hand lane (passing lane with a minimal shoulder) when I heard a terrible noise that sounded like I had a flat tire and the car began to pull to the left. I immediately slowed down and steered the vehicle onto the small shoulder on the left-hand side of the interstate. It was at this point I looked out my window (driver's window) and saw the entire left front wheel (not just the rubber tire) rolling by (west in the grassy median of I-90). The vehicle did not roll over, hit another vehicle, or get hit by another vehicle. After coming to a safe stop, I got out of the vehicle and saw that the left front (driver's side) wheel (not just the rubber tire) was gone. There were two (2) other passengers in the vehicle at the time that the wheel fell off who exited the vehicle out of danger of passing cars/trucks/semi tractor trailers on I-90. The vehicle was towed and to my knowledge has not been inspected by the manufacturer. The Hertz rental vehicle was only "inspected" by PurCo claims specialist via pictures as they did not have the vehicle in their possession. There were no warning messages, lamps, lights, or other symptoms prior to the wheel falling off. The wheel fell off on 7/8/2023 on Interstate 90 in South Dakota. After the wheel fell off, it rolled down the median of I-90 bounced up onto the westbound lane of I-90 and struck another vehicle causing that vehicle's airbags to deploy. There were four (4) occupants in that vehicle.

AS I WAS DRIVING DOWNHILL WITH MINIMAL SNOW ON THE GROUND, I TAPPED MY BRAKES ABOUT 7 TIMES BEFORE THEY LOCKED UP. I WENT TO TURN TO STAY ON THE ROAD AND THE STEERING WHEEL WOULDN'T BUDGE CAUSING ME TO GO OFF THE ROAD, INTO AN EMBANKMENT. VEHICLE WAS GOING ABOUT 5-10MPH WHEN THIS OCCURED ON A CITY STREET.

The contact owns a 2021 Mazda CX-9. The contact stated while driving at various speeds and turning, there was a popping sound coming from the front end of the vehicle. The front-end popping sound also occurred while driving over bumps in the roadway. The vehicle was taken to an independent mechanic who was unable to determine the cause of the failure. The vehicle was not repaired. The local dealer and manufacturer were not notified of the failure. The failure mileage was 68,811.