There are 4 owner-reported fuel system complaints for the 2016 Mazda Mazda3in NHTSA's database. These are unverified consumer reports and may not reflect confirmed defects.
Fuel Tank has corrosion that allows vapors to enter the passenger compartment.
Recently noticed the odor of unburned gasoline, both inside and outside the vehicle. When driving, the ventilation system would flush this away in a few moments, but this phenomenon is new within the past few weeks. Our mechanic (not the dealer) traced the issue to the fuel tank, where the port for the fuel pump and sensors is located on top. This area is accessible by removing the rear seat cushion and a cover plate. He showed me how the fuel pump and sensor module has rusted to the thread of the port, preventing removal of the assembly, and that the port flange itself has rusted and has pin-holes, allowing vapor to escape. He was able to put slight positive air pressure to the tank as a test, and was able to cause liquid fuel to escape from the holes. The tank was about 3/4 full at the time. This seems like a serious safety issue. The port and matching threaded parts (fuel pump / sensor module) that inserts there should be corrosion-proof. I can provide a photo of the affected area if needed; I would get the image file from my mechanic.
DURING HOT SUMMER MONTHS WHEN RUNNING ERRANDS (FOR EXAMPLE) WHICH WOULD REQUIRE STOPPING AND RE-STARTING THE VEHICLE SEVERAL TIMES, THE CABIN WILL BEGIN TO FILL WITH GAS FUMES. THIS WILL START ABOUT 30 MINUTES INTO THE TRIP. THE FUMES BECOME SO STRONG THAT I BECOME SICK AND HAVE A HEADACHE. YOU CAN SMELL FUMES INSIDE AND OUTSIDE OF THE VEHICLE. THIS DOES NOT HAPPEN DURING HIGHWAY TRAVEL. EVEN THOUGH THIS IS A RECALL ISSUE FOR THE 2016 MAZDA 3, FOR SOME REASON IT DOES NOT APPLY TO MY MAZDA 3. IF I WANT TO HAVE THIS REPAIRED, I WOULD HAVE TO PAY OUT OF POCKET FOR SOMETHING THAT SHOULD BE REPLACED BY MAZDA.
FUELING CAR AND PUMP AUTO-SHUTOFF DID NOT WORK CAUSING GASOLINE TO OVERFLOW THE TANK AND SPILL ON THE GROUND. WAS NOT HOLDING THE HANDLE OR ATTEMPTING TO TOP-OFF THE TANK. EXPERIENCED SAME ISSUE ONE WEEK LATER WITH 2016 MAZDA6 AT A DIFFERENT LOCATION.
Complaints are unverified consumer reports submitted to NHTSA. A high complaint count may reflect vehicle popularity, not defect severity. Data sourced from NHTSA public records.
Data synced from NHTSA on Apr 26, 2026