2021 Mazda Mazda3 Problems
Owner-reported complaints filed with NHTSA, grouped by component
Data refreshed
What this page shows
Everything below is an owner-reported complaint submitted to NHTSA about the 2021 Mazda Mazda3, grouped by the component NHTSA recorded on the report. These are not confirmed defects, and they are not recalls. NHTSA does not verify most reports before publishing them, and a category with more reports in it is not evidence that a part is defective.
Complaints are reports submitted by owners and drivers to NHTSA. They are not verified and do not establish that a defect exists.
Reports by component
Ranked by how many owner reports name each component category
- Engine1833.3%
- Driver assistance1018.5%
- Electrical611.1%
- Airbags47.4%
- Brakes47.4%
- Powertrain (other)35.6%
- Fuel system23.7%
- Body & structure23.7%
- Other / unspecified23.7%
- Seat belts11.9%
- Steering11.9%
- Suspension11.9%
Percentages are of component mentions. A single complaint can name more than one component, so these do not sum to the total complaint count.
Each component in detail
What the reports in each category say, in the owners' own words
Engine
Reports naming the engine itself — including stalling, misfires, oil consumption, cooling and internal engine components.
From owner reports, verbatim
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.
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 and stuttering sounds, and the temperature gauge within the vehicle failed to rise to optimal range. As this occurred while the vehicle was in use (safety concern), though I was pushing the gas there would be delayed response due to improper temperature, which increased the risk for an accident to occur.
Driver assistance
Reports naming forward-collision avoidance, lane keeping, back-over prevention, cruise control and related electronic driver-assistance systems.
From owner reports, verbatim
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 unexpectedly veering to the right and accelerating without driver input. Given these recurring reports and my own experience, I strongly suspect that a manufacturing defect—whether mechanical, electronic, or software-related—may have contributed to this accident.
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 to drive the vehicle, they would be able to observe the malfunction. The dealer has been made aware on many occasions, though they never documented it and only suggested that I turn the feature off, which automatically turns itself on upon ignition. There are no warnings that there is a malfunction; you only know there is an error once an alert pops up thinking you’re missing a curve and attempts to turn your steering wheel though there is no curve. This issue has persisted over the life of the vehicle.
Electrical
Reports naming the electrical system — wiring, battery, charging, control modules, infotainment and electrical accessories.
From owner reports, verbatim
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 unexpectedly veering to the right and accelerating without driver input. Given these recurring reports and my own experience, I strongly suspect that a manufacturing defect—whether mechanical, electronic, or software-related—may have contributed to this accident.
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.
Too few reports in this category for a page of its own — they appear in the full complaint list.
Airbags
Reports naming the air-bag system — deployment behaviour, inflators, sensors and warning lights.
From owner reports, verbatim
Air bag malfunction light comes on a and goes off multiple times while driving
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.
Too few reports in this category for a page of its own — they appear in the full complaint list.
Brakes
Reports naming service brakes, the antilock braking system, brake hoses, master cylinders or the parking brake.
From owner reports, verbatim
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.
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.
Too few reports in this category for a page of its own — they appear in the full complaint list.
Powertrain (other)
Powertrain reports that are not specifically the engine or transmission — driveshafts, axles, transfer cases and differentials.
From owner reports, verbatim
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
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 the problem.
Too few reports in this category for a page of its own — they appear in the full complaint list.
Fuel system
Reports naming fuel storage or delivery — tanks, pumps, lines, injectors and fuel leaks.
From owner reports, verbatim
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
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 shaking when applied. Dealer informed me that they do not warranty the OEM brakes that came on my car, however Mazda Corporate informed me that they do. I do not feel safe driving this car knowing the car may combust and harm me and others on the road. The brakes also do not inspire confidence. A complaint has been filed with Mazda Corporate.
Too few reports in this category for a page of its own — they appear in the full complaint list.
Body & structure
Reports naming the vehicle structure, frame, body panels, doors, hood and trim.
From owner reports, verbatim
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 covering, so rust is an unlikely cause.
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
Too few reports in this category for a page of its own — they appear in the full complaint list.
Other / unspecified
Reports whose component NHTSA recorded as unknown, or that do not map to one of the categories above.
From owner reports, verbatim
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.
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!
Too few reports in this category for a page of its own — they appear in the full complaint list.
Seat belts
Reports naming seat belts, buckles, retractors and pretensioners.
From owner reports, verbatim
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 already been replaced once under warranty at a Mazda dealership. Now the second seatbelt receptacle is starting to do the same thing again after about 6 months of use. I fear that even if I get it replaced a second time, this will just continue to happen. Perhaps there is a manufacturing defect. As this issue continues to get worse, I fear that this creaking will develop into a major failure with the seatbelt connection itself.
Too few reports in this category for a page of its own — they appear in the full complaint list.
Steering
Reports naming the steering system — racks, columns, power-steering assist and steering linkage.
From owner reports, verbatim
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 unexpectedly veering to the right and accelerating without driver input. Given these recurring reports and my own experience, I strongly suspect that a manufacturing defect—whether mechanical, electronic, or software-related—may have contributed to this accident.
Too few reports in this category for a page of its own — they appear in the full complaint list.
Suspension
Reports naming suspension components — springs, struts, shocks, control arms and related hardware.
From owner reports, verbatim
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.
Too few reports in this category for a page of its own — they appear in the full complaint list.
Higher-selling and older vehicles accumulate more reports. Counts are not failure rates and are not directly comparable between vehicles that sold in very different numbers.
Elsewhere on this vehicle
Data sources
- NHTSA Office of Defects Investigation — owner-reported complaints and the components recorded on them
Data on this page last refreshed .