Mazda MAZDA3 sudden acceleration problems

Filed Jan 22, 2026 · Brakes, Electrical · CA · crash · 1 injury

On 14th, 2026, while traveling at approximately 60 mph on the northbound 55 Freeway near the Katella exit, my vehicle suddenly began to shake violently without any prior warning. In response, I attempted to slow down by applying the brakes; however, the speedometer rapidly increased even as I maintained firm pressure on the brake pedal. Immediately afterward, the vehicle pulled sharply to the left, causing a complete loss of steering control and resulting in a collision with the center median barrier. Despite the force of the impact, the airbags did not deploy, raising additional concerns about potential safety system failures. At no point before the incident were there warning lights, alerts, or indications of mechanical or electronic issues. The vehicle had also undergone its regularly scheduled maintenance at the Tustin Mazda dealership on January 2nd, 2026, just prior to the accident. Given the sudden shaking, unintended acceleration, loss of braking effectiveness, steering failure, and non‑deployment of airbags, I believe this incident may involve one or more manufacturer defects affecting critical safety systems. I respectfully request that the federal safety agency investigate this matter. I also believe the vehicle’s Event Data Recorder (EDR) may contain information relevant to identifying the root cause of these failures.

Filed Jun 17, 2021 · NY

I have been experiencing unintended acceleration while in D (drive) but stopped with my foot on the brake. For instance, when fully stopped at a light, the car will suddenly experience a small burst of acceleration and propel forward. I see the engine rpm go up when this occurs even though I am stopped. This is very scary and uncomfortable as I feel like I lose control of the car during those times and can potentially hit another car or person in front of me.

Filed Feb 17, 2020 · Fuel system, Steering · 2,802 miles · MD · crash

Jan. 23, 2020. 10:45 am. I was on my street, a narrow residential street, preparing to back in my garage. In order to do that on this narrow street, I touched the lip of the driveway across the street. Speed well under 3 MPH. When I did so, my car suddenly sharply accelerated and at the same time swerved to the right. The acceleration and swerve drove the car into the townhouses across the street from my house. The driveways are very short, barely a car's length. After crashing, I could feel the car still accelerating. I quickly switched the car into park and the spontaneous acceleration continued. In order to stop in I had to turn the car off. When the towing company turned the car on later it immediately started to spontaneously accelerate and surge forward again. The mazda dealer and insurance inspector explained to me that there is a sensor: when a wheel encounters what it perceives to be an obstacle, it 'tosses' all the power to that wheel and accelerates. These driveways have a small lip at the edge. This sensor reacted to it in a way that caused my car to crash. The car was totaled and the townhouses across the street damaged. Thank heaven there was no one outside or they would have been killed. This needs to be investigated, recalled and changed.

Filed May 28, 2019 · Transmission · 95,000 miles · OR

Tl* the contact owns a 2012 mazda 3. While driving various speeds, the transmission skipped gears and the rpms accelerated without warning. In addition, the check engine warning indicator illuminated. The failures occurred intermittently. The dealer was not contacted. An independent mechanic changed the oil and diagnosed that the transmission needed to be repaired. The transmission had not been repaired. The manufacturer was made aware of the failure. The failure mileage was 95,000. The VIN was unavailable.

Filed Feb 28, 2019 · Acceleration, Transmission · 63,000 miles · MI

10+ incidents of sudden unintended acceleration since aug 2018. Always at freeway speed of traffic, I.e. 70-75mph. Occurs when intentionally decelerating (easing off the gas pedal and initiating braking). Rpms jump to 7 or 8. Acceleration immediately drops and steads after tapping/applying pressure to brakes. Has been taken ralph thayer dealership 3 times -- aug2018, jan2019, feb2019. Each time vehicle kept for a week but unable to duplicate issue. Data recorder was installed in jan2019. Despite a several minute long episode on feb 22, 2019 in which the car behaved erratically (buckling and jolting) and wouldn't accelerate more than 60 MPH while the rpms were high (4-5) for several minutes, this was somehow not sensed by the data recorder. My own guess is an issue with the PCM or the automatic transmission control module. Have suas affected transmission? Seems to be a known issue yet the dealer/mazda reaction is perfunctory at best. No commitment to resolve. E.g. Because my driving was limited while the recorder was in, I requested that it be left in for 3 months. Mazda refused, stating that if it happens again (and it will), they'll reinstall the recorder. That a collision hasn't happened is just luck. A serious accident caused by this vehicle is imminent since these issues adversely affect the ability to control the vehicle. I also don't relish being my own crash test dummy. There is nothing they can do beyond a series of expensive parts replacements based on their guesses? I have some video and photos per their request, but note that attempting to photograph or video the dashboard while driving is an extra bullet in what already feels like russian roulette. I've attached a summary of events provided to mazda in january and the most recent mechanic's report. $800 suggested for guess-based TCM replacement, $240 inconclusive tests, no loaner provided.

Filed Aug 4, 2018 · Acceleration, Brakes · 10,000 miles · PA · crash

The engine began revving high as I took my foot off the accelerator and apply the brakes as I approached a traffic red light. I put the car in neutral to see if by tapping the gas pedal it would stop revving. It did not. With my foot on the brake pedal to the floor, I put the car in drive and the car sped forward despite my foot on the brake pedal. I went through a red light trying to make a left turn on to a major highway, crossed a median strip, clipped a vehicle in the rear, turned the car trying to avoid collisions with other cars, went off the road hitting utility pole and transformer box on the opposite side of the highway, finally coming to rest with air bags deployed on the driver side. This happened on july 8, 2018, a sunday afternoon. No one was hurt, but obviously shaken and confused how my brakes could fail on a car recently in for its 10000 mile scheduled maintenance 9 days prior. Researching this on line found similar incidents of this occurring with mazda 3 vehicles and other manufacturers (I.e. Toyota). Referred to as sudden unintended acceleration (sua). There are many reported cases of sua, some where drivers are at fault. My case was clearly mechanical defect related.

Filed Aug 21, 2017 · Acceleration · 26,800 miles · MD · crash

I was turning slowly into a parking space between two parked cars with my foot on the brake. Approximately 1/4 to 1/3 of the way into the space the car suddenly accelerated (my foot still on the brake). It jumped the curb, crossed over the sidewalk, "took out" 2 pilings and large flower box and then stopped. Engine was still running. It happened in a matter of seconds and I had no time to react in any way. Car had to be winched off of the pilings which now have to be reset approx. 15" - 18" into the ground. I have photos taken by a neighbor, but do not know how to upload them. Tow truck driver took some to show to the insurance adjuster.

Filed Jul 27, 2016 · Acceleration, Airbags · 12,200 miles · MD · crash

My 2014 mazda 3 suddenly and unexpectedly accelerated and crashed into a parked truck. There was an eye-witness. Here is what happened: I was driving on a quiet, dead-in street accompanied by my husband. I turned left into the turn around area at the end of the street. As I was coming to a stop, with my foot on the brake, the car suddenly accelerated'going very fast, very quickly. It leapt over the curb, narrowly missed a tree and a fire hydrant, passed back over the street I had been on moments earlier, and crashed into a parked pick-up truck. The air-bags did not deploy. All of this happened in 2 to 3 seconds. We were not hurt. The eye witness was in his yard, which adjoins the turn-around area. After the accident, he came over and asked if I was ok. He asked me if I could turn my car off. The eye witness later told me he had seen the whole thing and that I never had control over the car. He said he told the police that he was watching me turn my car into the turnaround area and saw the car suddenly accelerate. He wanted me to know that there was a mechanical problem with my car. He told me that when he approached the car, it was revving and still trying to accelerate into the truck, even though my feet were nowhere near the pedals. That was why he asked if I could turn the car off. I remembered before turning the car off, that I could hear the whine of the engine as it sounds when it is at high rpms. The unexpected acceleration and the fact that the air-bags did not deploy are both serious safety concerns. The car was towed to the mazda dealership and the service department contacted mazda corporation who sent an engineer to check it out. They said they could not find a problem, but they put an event data recorder on the car to monitor it. They drove the car for a few days and nothing showed up. The dealer bought the car back.

Filed Jul 11, 2016 · Acceleration, Transmission · 20,000 miles · OH · crash · 1 injury

As I was turning into a parking spot to park my car, the car accelerated on its own and ran into a concrete wall. I have had issues with this car's programming, including when I took my car in to get fixed after the safety recall in january '16. As I realized the car was accelerating - and pushing on the brake would not stop it - I lifted the emergency brake. The crash ultimately stopped the car - not the brake or emergency brake, and the airbag deployed. Less concerned about the damage to the outside of the car, and more concerned that I had zero control over the car and any ability to stop it.

Filed May 2, 2016 · Acceleration · 22,000 miles · NV · crash

Tl* the contact owns a 2011 mazda 3. While attempting to park the vehicle, it experienced unintended acceleration even when the brake pedal was depressed. The vehicle crashed into a pole in a dog park. There were no injuries. The failure occurred without warning. The vehicle was towed to the dealer. It had not been determined if the vehicle was destroyed. The manufacturer was notified of the failure. A police report was filed. The failure mileage was approximately 22,000. The VIN was not provided.