2021 Mazda Mazda3 Problems & Owner Complaints

Engine 18

“Spontaneous loss of power while driving on highway. Check engine light came on. Speed limited by car. Continues to vibrate especially at idle from cold start. Code P0304 intermittently popping up.”
NHTSA complaint #11656416, 2025

“The thermostat malfunctioned on this vehicle, resulting in the thermostat remaining open and providing excess coolant to the engine, which in turn damaged internal components of the engine (compromises safety), decreased fuel economy, increased emissions (compromised safety), and decreased the life of the engine within the vehicle. It is available for inspection upon request. The vehicle has been inspected by an independent mechanic and will be inspected by the Mazda dealership in 7 days. There were no prior warnings until the engine malfunction notice appeared, the vehicle began to make jolts…”
NHTSA complaint #11644041, 2025

“The contact owns a 2021 Mazda Mazda3. The contact received notification of an unknown Class Action Lawsuit Number however, the part to do the repair was unavailable. The contact stated that the manufacturer exceeded a reasonable amount of time for the repair. The manufacturer was made aware of the issue. The contact had not experienced a failure. Parts distribution disconnect.”
NHTSA complaint #11631026, 2024

Forward Collision Avoidance 7

“At red light, close behind car in front of the mazda. After light turns green, start driving the mazda after car in front moves forward. Although the car in front is moving forward at a higher rate of speed, increasing the distance between it and the mazda, the automatic emergency brake kicks on and stops the vehicle abruptly. Luckily the cars behind the mazda reacted in time and did not rear end it.”
NHTSA complaint #11613907, 2024

“During a night drive, travelling approx. 40mph, car warning system audio blared a warning and suddenly braked causing car to skid (was raining) and causing driver to also jolt forward with momentum. There was very little time between beginning of audio warning and car slamming on brakes.”
NHTSA complaint #11504587, 2023

“Vehicle detects cars in other lane as an impeding collision in turns, activates emergency braking when no collision is imminent.”
NHTSA complaint #11478293, 2022

Unknown Or Other 7

“The driver window, upon attempted to be let up, will start to go up then go all the way down, ignoring the function to go up. This is a safety concern, as harsh temperatures and foreign objects are able to enter the vehicle cabin at any time, including driving. The problem has been reproduced by a dealer, and the vehicle is available for inspection upon request. There are no warning indicators for this issue beyond witness the failure occur in real time.”
NHTSA complaint #11644043, 2024

“While driving at a normal speed on a clear, sunny day with no other vehicles close by, I heard a loud crash sound and my car's sunroof unexpectedly shattered. The inside glass panel looks like it's shattered and it caused tiny glass shards to fall inside the vehicle onto my right arm and the surrounding area. I closed the cover to prevent more from falling. This occurred without any prior warning, signs, or symptoms such as unusual noises or warning lights from the car. This incident posed a significant safety risk, not only due to the distraction, shock of the sudden noise, glass falling, in…”
NHTSA complaint #11595814, 2024

“My 2021 Mazda 3 was bought used in August 2023 and is about a year old in my possession. it has been at the Mazda dealership for repairs multiple times since August 2023. it dangerously stalls and hesitates when trying to accelerate from a stop position. When the brake pedal is released and I start to accelerate like merging onto highways,the car rumbles or shakes slightly and then shuts off. I Came across a review online that had the exact same problem and it stated a PCM update solved the issue. I have been to the dealer frequently since purchased and they kept my car for over a week and…”
NHTSA complaint #11626518, 2023

Electrical System 6 1 crash 2 fire

“The contact owns a 2021 Mazda Mazda3. The contact stated that while driving at various speeds the passenger front side tire was flat which caused the contact to veer to the shoulder. The contact towed the vehicle to the dealer where the tire was inspected as the technician informed the contact that the tire was on backorder and no replacement tire was available. The vehicle then was towed back to the contact resident however was informed by the towing company that the vehicle abrupted in flames on the flatbed. The fire department was contacted and extinguished the flames. No police report was…”
NHTSA complaint #11431973, 2021 · fire

“TL* THE CONTACT OWNS A 2021 MAZDA MAZDA3. THE CONTACT STATED WHILE THE VEHICLE WAS AT A STAND STILL AT A PARKING LOT, WHEN IT CAUGHT FIRE. THE FIRE DEPARTMENT WAS ABLE TO EXTINGUISHED THE FIRE AND FILED A REPORT. THE POLICE WAS AT THE LOCATION BUT DID NOT FILE A REPORT. THE VEHICLE WAS DRIVABLE BUT WAS TOWED AT A TOW LOT. THE CONTACT CALLED LOCAL DEALER MORONG FALMOUTH MAZDA (187 US-1 #1311, FALMOUTH, ME 04105: (207) 781-4020) AND WAS MADE AWARE OF THE FAILURE. THE VEHICLE HAD NOT BEEN DIAGNOSED OR REPAIRED. THE MANUFACTURER HAD BEEN INFORMED OF THE FAILURE. THE FAILURE MILEAGE WAS APPROXIMATE…”
NHTSA complaint #11403223, 2021 · fire

“During the incident, the vehicle exhibited an uncontrollable malfunction—the steering wheel suddenly jerked sharply to the right while accelerating violently, leaving me unable to steer or brake effectively, the car was looking forward. The car ultimately came to a stop upon colliding with a truck parked diagonally in front of me. After impact, I observed that the front tires remained stuck in a turned-right position, with the steering wheel also locked in that position. This was not an isolated event. Multiple reports from Mazda owners describe similar experiences with their vehicles unexpect…”
NHTSA complaint #11645615, 2025 · crash

Air Bags 4 1 crash 1 injury

“The vehicle was badly rear ended and the airbags didn't deploy. The dashboard indicated an "airbag malfunction" after the collision happened. The failure of the airbags put myself and my passengers at serious risk; if we weren't wearing our seatbelts, which we were, we would have been gravely injured. The vehicle is less than a year old and still under warranty.”
NHTSA complaint #11468801, 2022 · crash · 1 injury(ies)

“Air bag malfunction light comes on a and goes off multiple times while driving”
NHTSA complaint #11482854, 2022

“My car started to show a warning on the dashboard that the airbag system is malfunctioning. The alarm would come on for a few seconds, then turn off, then repeat like that multiple times every drive. At the time it started, my car had less than 500 miles on it, and it continued after that until I got it fixed. I took it to the Mazda dealership where I bought it, and they said it was a short circuit to the driver's side airbags. They told me that could have caused the airbags to deploy prematurely or not at all in an accident. I am also a part of a Mazda 3 community and am active on the forums,…”
NHTSA complaint #11460158, 2021

Service Brakes 4

“Brakes are underpowered especially when hot. Drove 20-30 minutes in traffic and when decelerating from 60 mph highway in turn lane to turn into neighborhood the brakes felt very soft . Car only has 28k miles on it and pads have plenty of life left. Have seen similar complaints on online forums.”
NHTSA complaint #11595331, 2024

“During a night drive, travelling approx. 40mph, car warning system audio blared a warning and suddenly braked causing car to skid (was raining) and causing driver to also jolt forward with momentum. There was very little time between beginning of audio warning and car slamming on brakes.”
NHTSA complaint #11504587, 2023

“Strong unburnt fuel smell had just started at 6700 miles. Mazda Dealership stated that they would not be looking at my car and that gas smells are normal... After this encounter, I had 2 mechanics look at my car. Both had concluded that the smell predominantly comes from near the rear driver wheel, under the body, and that it is an extremely dangerous situation. I am a full time student and do not feel safe driving this car to class but I have no choice since Mazda is neglecting this issue. I also reported to the dealer that my brakes seem to be defective since they are causing excessive sha…”
NHTSA complaint #11486305, 2022

Lane Departure 3

“When this feature is left on in my vehicle, it will detect curves, vehicles, and objects that are not there, and as a result, will attempt to turn my steering wheel (safety concern). I have had to keep this feature turned off to prevent it wrecking the car, because I could be on a straight road, and it will detect a curve that isn’t there and begin turning the wheel, which could result in a fatal accident if not corrected and disabled by the driver. It is available for inspection upon request. As the dealer has not driven the vehicle, they have not recreated the error, however if anyone were t…”
NHTSA complaint #11644042, 2021

“The error code "B14FO-76 FORWARD SENSING CAMERA DEVIATION - WRONG MOUNTING POSITION" was discovered, and verified, by a Safelite Auto Glass service center when the 2021 Mazda 3 was in for a repair (stone chip) to the windshield on September 21, 2021. There were no warning messages nor lights to alert the driver as to the improper installation/mounting of this device. There has been no known modification to nor obstruction of the FSC -- its condition is now as it was received new from the dealer. Improper mounting ("Wrong Mounting Position") of the Forward Sensing Camera affects multiple safety…”
NHTSA complaint #11434720, 2021

“PASSENGER SIDE BLIND SPOT WARNING FUNCTIONS SPORADICALLY. IT SOMETIMES DETECTS VEHICLES AND SOMETIMES DOES NOT WHILE DRIVING AT THE SAME SPEED.”
NHTSA complaint #11396149, 2021

Power Train 3

“My rear differential case cracked, anytime the four wheel drive system was engaged the entire drivetrain would lock up. Luckily we were only on side roads so going less than 30 mph if we had been on the highway when this happened we could have been in an accident or lost control. The dealer did confirm the problem and it was fixed under an extended warranty. There was no warning just all of a sudden a loud bang and all the wheels locked up. I have a copy of the video inspection done at the dealer if there's anyway to send that. I can get a copy of the repair invoice if needed”
NHTSA complaint #11713224, 2025

“I was driving when all the sudden there was a loud bang sound. The differential housing cracked. The when awd is demanded the rear diff was was locking up instead of engaging. Luckily we were just on city streets and not on the highway as this rear wheel locking up could cause a crash. Mazda wasn't very helpful with the replacement. Luckily I had a aftermarket warranty but it only paid for a used replacement, which is also failing. I have read lots of stories of this rear differential failure across all types of Mazda's from this era and really wish they would do the correct thing and resolve…”
NHTSA complaint #11663288, 2025

“Radiators are failing 3 years after the warranty period. Its leading to coolant lost and perhaps overheating the engine.”
NHTSA complaint #11627559, 2024

Fuel/Propulsion System 2

“Car emits a very audible squeak when shifting right above 30mph and 40mph, car surges at lower and constant speeds, tach will slowly drop when applying throttle, surge slightly, then function as normal again”
NHTSA complaint #11499817, 2023

“Strong unburnt fuel smell had just started at 6700 miles. Mazda Dealership stated that they would not be looking at my car and that gas smells are normal... After this encounter, I had 2 mechanics look at my car. Both had concluded that the smell predominantly comes from near the rear driver wheel, under the body, and that it is an extremely dangerous situation. I am a full time student and do not feel safe driving this car to class but I have no choice since Mazda is neglecting this issue. I also reported to the dealer that my brakes seem to be defective since they are causing excessive sha…”
NHTSA complaint #11486305, 2022

Structure 2

“A bolt head underneath the car snapped for the steering mechanism. The problem was indicated by a clanking noise I heard for many 1000s of miles. It's been as long as I remember, but I had no idea what it really meant. It's 2.7 years old with 30,653 miles right now. There were no warnings. The wheel could have come off at any moment I was driving it. The bolt was likely over-torqued or had a manufacturing defect causing it to snap. I have pictures for when the car was propped up at a technician. One side is completely non rusted. The other side is showing rust ONLY from where the bolt was c…”
NHTSA complaint #11572078, 2024

“Car emits a very audible squeak when shifting right above 30mph and 40mph, car surges at lower and constant speeds, tach will slowly drop when applying throttle, surge slightly, then function as normal again”
NHTSA complaint #11499817, 2023

Vehicle Speed Control 2 1 crash

“During the incident, the vehicle exhibited an uncontrollable malfunction—the steering wheel suddenly jerked sharply to the right while accelerating violently, leaving me unable to steer or brake effectively, the car was looking forward. The car ultimately came to a stop upon colliding with a truck parked diagonally in front of me. After impact, I observed that the front tires remained stuck in a turned-right position, with the steering wheel also locked in that position. This was not an isolated event. Multiple reports from Mazda owners describe similar experiences with their vehicles unexpect…”
NHTSA complaint #11645615, 2025 · crash

“Context: ADAS was not on. Lane keep assist is disabled in system settings entirely as it is dangerous. Blinkers were on, I was pulling out from parallel parking into left turn lane onto a straight road with slight incline. Car is of the Turbo trim on stock tires. Upon finishing pulling out of parallel parking spot and gassing the car, torque vectoring or some underlying collision avoidance may have phantom activated. I felt torque shift to the wrong tires, unsettling the car, and the wheel -- with no human input -- jerked to the left to force me into the lane left of intended. I applied throt…”
NHTSA complaint #11448467, 2022

Wheels 2

“For the past 7 months (since July 2023) the passenger rear tire keeps loosing air pressure about every two weeks requiring more air. It always drops to 10 points below the other tires. The tires have been rotated twice so it is not a problem with the tire. I believe there is a recall for the same or similar issue on Mazda 3s just not including my VIN#. I brought my car to good year a few times unable to stop this from happening.”
NHTSA complaint #11572875, 2023

“This new car has less than 8000 miles on it and suddenly 3 of 4 BRIDGESTONE TIRES Turanza el440 215/45R18 89 have sidewall bubbles. Interesting that there are a ton of issues w sidewall Bridgestone tires on line yet the dealership keeps claiming the car must have been run over a median? Without any damage anywhere on the car? Come on.. it is clearly a manufacturer defect. They have history with sidewall bubbling. Consumers getting shafted at best and maimed at worst. Do something please!”
NHTSA complaint #11479464, 2022

Seat Belts 1

“The latches inside the driver's seatbelt receptacle feel like they wear out over time. The only reason I can tell is because there is a really noticeable creaking that develops from inside the receptacle while the seatbelt is connected. This is worse for drivers with bigger waists and as the driver's waist continues to tug on the seatbelt during operation, the creaking gets worse over time. There are no electronic warnings. The seatbelt still properly connects and there are no electronic messages saying that anything is wrong with the seatbelt. My driver's original seatbelt receptacle has al…”
NHTSA complaint #11500412, 2023

Steering 1 1 crash

“During the incident, the vehicle exhibited an uncontrollable malfunction—the steering wheel suddenly jerked sharply to the right while accelerating violently, leaving me unable to steer or brake effectively, the car was looking forward. The car ultimately came to a stop upon colliding with a truck parked diagonally in front of me. After impact, I observed that the front tires remained stuck in a turned-right position, with the steering wheel also locked in that position. This was not an isolated event. Multiple reports from Mazda owners describe similar experiences with their vehicles unexpect…”
NHTSA complaint #11645615, 2025 · crash

Suspension 1

“At 31,000 miles the control arm lower ball joints are torn on both lower. They must be replaced. This is a safety hazard. This should not be an issue with low mileage on this car.”
NHTSA complaint #11695896, 2025