Owners have filed 78 complaints
about the 2018 Mazda MAZDA6 with NHTSA between 2019 and 2026.
The largest single group is the engine & cooling.
Across this model's run it ranks 14 of 18 worst.
The letter says how bad. This says what kind — whether this year drew
an unusual number of complaints, unusually dangerous
ones, or failures that arrived unusually early.
The dashed ring is 50 — the national norm. Further out is worse.
Complaint volume — 24
Against the median year of the Mazda MAZDA6. 50 means typical for this
model; 100 means roughly double.
Severity — 33
6.4% of these complaints
involved a crash, fire, injury or death, against a national rate of
9.7%.
Early failure — 100
86% of failures with a mileage on record happened under
36,000 miles, against a national rate of
29%.
Odometer readings owners gave when they filed. About half of all
complaints include one.
Under 1,000 miles
313.6%
1,000 – 9,999 miles
627.3%
10,000 – 24,999 miles
836.4%
25,000 – 49,999 miles
313.6%
50,000 – 74,999 miles
14.5%
75,000 – 99,999 miles
14.5%
When owners complained
A spike years after the car went on sale usually means a part wearing
out on schedule across the whole fleet — the kind of pattern no single
owner can see from inside their own car.
Mar 2019peak 4Aug 2026
Recalls on the 2018 Mazda MAZDA6
A complaint is one owner's allegation. A recall is the point at which
the manufacturer or a regulator agreed the defect is real and dangerous
enough to fix for free — however old the car is.
United States — NHTSA
21V875000
FUEL SYSTEM, GASOLINE:DELIVERY:FUEL PUMP
Mazda North American Operations (Mazda) is recalling certain 2018 Mazda3, Mazda6, 2019 CX-3, 2018-2019 MX-5, CX-5, CX-9, and 2019-2020 Mazda2 vehicles. The impeller inside the low-pressure fuel pump may crack and deform, potentially causing the fuel pump to fail.
Risk: Fuel pump failure may cause an engine stall, increasing the risk of a crash.
19V497000
ENGINE
Mazda North American Operations (Mazda) is recalling certain 2018-2019 CX-5, Mazda6, and 2019 Mazda3 vehicles. A software error in the powertrain control module (PCM) may cause the engine to stall.
Risk: An unexpected stall increases the risk of a crash.
Canada — Transport Canada
Canada runs its own recall programme, and its campaigns do not
always mirror the American ones.
Recall 202169620,762 units in Canada
Fuel System
Issue: On certain vehicles, the fuel pump could fail. If this happens, the engine may run rough or may not start and the check engine light may turn on. This could also result in a sudden loss of engine power while driving. Safety Risk: A sudden loss of engine power while driving could increase the risk of a crash. Corrective Actions: Mazda will notify owners by mail and instruct you to take your vehicle to a dealer to replace the fuel pump.
Recall 201932242,662 units in Canada
Engine
Issue: On certain vehicles, a software error in the Powertrain Control Module (PCM) could cause the valve clearance adjuster not to work properly. This could result in internal engine damage. If this happens, the engine may misfire and lose power. In the worst case, the engine may stall while driving without the ability to restart it. The malfunction indicator light (MIL) may also turn on in the instrument cluster. Safety Risk: A sudden loss of engine power could increase the risk of a crash. Corrective Actions: Mazda will notify owners by mail and instruct them to take their vehicle to a dealer to update the PCM software.
Reports where the owner recorded a crash, a fire, an injury or a death.
Fresno, CAFire
UNKNOWN OR OTHER
MY MAZDA6 SPONTANEOUSLY CAUGHT ON FIRE WHILE IT WAS PARKED ON A STREET AND COMPLETELY BURNED DOWN. THE FAULT/PROBLEM CAUSE IS UNKNOWN AT THIS TIME BUT I SUSPECT THERE WAS WIRING/ELECTRICAL FAULT AND MANUFACTURING AND DESIGN DEFECT. BOTH THE SHERIFF'S DEPARTMENT AND FIRE DEPARTMENT WERE INVOLVED IN ASSISTING ME IN THIS INCIDENT. I AM STILL WAITING FOR REPORTS FROM LAW ENFORCEMENT/FIRST RESPONDERS. MAZDA HAS REFUSED TO ADDRESS THIS SITUATION WITHOUT ME PROVIDING THEM WITH AN "INSPECTION REPORT SUPPORTING THE CLAIM A DEFECT WAS PRESENT AND SAID DEFECT CAUSED THE FIRE." AS I WAS ONLY A LESSEE OF THE VEHICLE, I HAVE NO POSSESSION OF THE VEHICLE AND, THEREFORE, I CANNOT ORDER AN INSPECTION ON THE VEHICLE. MAZDA IS ACTING IN BAD-FAITH.
NHTSA complaint #11349943 — an unverified report by a vehicle owner.
Fresno, CAFire
ELECTRICAL SYSTEM
MY MAZDA6 SPONTANEOUSLY CAUGHT ON FIRE WHILE IT WAS PARKED ON A STREET AND COMPLETELY BURNED DOWN. THE FAULT/PROBLEM CAUSE IS UNKNOWN AT THIS TIME BUT I SUSPECT THERE WAS WIRING/ELECTRICAL FAULT AND MANUFACTURING AND DESIGN DEFECT. BOTH THE SHERIFF'S DEPARTMENT AND FIRE DEPARTMENT WERE INVOLVED IN ASSISTING ME IN THIS INCIDENT. I AM STILL WAITING FOR REPORTS FROM LAW ENFORCEMENT/FIRST RESPONDERS. MAZDA HAS REFUSED TO ADDRESS THIS SITUATION WITHOUT ME PROVIDING THEM WITH AN "INSPECTION REPORT SUPPORTING THE CLAIM A DEFECT WAS PRESENT AND SAID DEFECT CAUSED THE FIRE." AS I WAS ONLY A LESSEE OF THE VEHICLE, I HAVE NO POSSESSION OF THE VEHICLE AND, THEREFORE, I CANNOT ORDER AN INSPECTION ON THE VEHICLE. MAZDA IS ACTING IN BAD-FAITH.
NHTSA complaint #11349943 — an unverified report by a vehicle owner.
Fresno, CAFire
ENGINE
MY MAZDA6 SPONTANEOUSLY CAUGHT ON FIRE WHILE IT WAS PARKED ON A STREET AND COMPLETELY BURNED DOWN. THE FAULT/PROBLEM CAUSE IS UNKNOWN AT THIS TIME BUT I SUSPECT THERE WAS WIRING/ELECTRICAL FAULT AND MANUFACTURING AND DESIGN DEFECT. BOTH THE SHERIFF'S DEPARTMENT AND FIRE DEPARTMENT WERE INVOLVED IN ASSISTING ME IN THIS INCIDENT. I AM STILL WAITING FOR REPORTS FROM LAW ENFORCEMENT/FIRST RESPONDERS. MAZDA HAS REFUSED TO ADDRESS THIS SITUATION WITHOUT ME PROVIDING THEM WITH AN "INSPECTION REPORT SUPPORTING THE CLAIM A DEFECT WAS PRESENT AND SAID DEFECT CAUSED THE FIRE." AS I WAS ONLY A LESSEE OF THE VEHICLE, I HAVE NO POSSESSION OF THE VEHICLE AND, THEREFORE, I CANNOT ORDER AN INSPECTION ON THE VEHICLE. MAZDA IS ACTING IN BAD-FAITH.
NHTSA complaint #11349943 — an unverified report by a vehicle owner.
at 18,000 milesChico, CACrash1 injured
SEAT BELTS
TL* THE CONTACT OWNS A 2018 MAZDA 6. WHILE THE CONTACT'S FRIEND WAS DRIVING 55 MPH, HE VEERED OFF THE SIDE OF THE ROAD INTO A DIRT PATCH, AND STRUCK AN OBJECT. THE AIR BAGS DEPLOYED AND THE DRIVER'S SEAT BELT UNBUCKLED UPON IMPACT. THE AIR BAG DEPLOYMENT BURNED THE CONTACT'S RIGHT UNDERARM. MEDICAL ATTENTION WAS NOT RECEIVED. A POLICE REPORT WAS NOT FILED. THE CONTACT'S FRIEND WAS ABLE TO DRIVE THE VEHICLE BACK TO HIS APARTMENT. THE VEHICLE WAS NOT DIAGNOSED OR REPAIRED. THE MANUFACTURER WAS NOTIFIED OF THE FAILURE AND DID NOT ASSIST. THE DEALER WAS NOT CONTACTED. THE FAILURE MILEAGE WAS APPROXIMATELY 18,000. *DT CONSUMER STATED PARTIAL RETRACT DUE TO PRETENSIONER FIRING. CANNOT BUCKLE ' 8 IN TOO SHORT. BOTH HANDS ON STEERING WHEEL. WEIRD SEAT BELT UNLATCHED.
NHTSA complaint #11282286 — an unverified report by a vehicle owner.
The most recent complaints
In the owners' own words, exactly as filed with NHTSA.
Madison, VA
ENGINE
The car only has 70k miles on it. The engine started smoking under the hood. Immediately stopped to look. There was oil leaking but I could not see from where. I took it across the street to the Toyota dealership and had them look at it. They explained to me that there was a crack in the cylinder head and oil was leaking everywhere. Potentially causing a fire or even an explosion. The old was leaking all over the exhaust manifold and engine. I had my 2 toddlers in the car not long before this happened. This is extremely unacceptable. Currently Mazda is saying it will be 7200 to replace the engine and that cost is on me. I think that is absolutely absurd being there are only 70k miles on the car and I bought it brand new. I also kept up with all of the required maintenance.
NHTSA complaint #11755535 — an unverified report by a vehicle owner.
Arnold, MD
VEHICLE SPEED CONTROL
Got error message that said "Forward Smart City Brake Support Malfunction" slso fot "smart brake malfunction" while driving. The ac stopped, the car speedometer kept going from 50 to zero. The car died and couldn't open doors, windows. Lost steering while driving. We were able to get off road and restart and fine for 2 weeks. While at still light tonight, the car turned off. Windows were up, couldn't open door, emergency blinkers would not come on. This is very dangerous.
NHTSA complaint #11753644 — an unverified report by a vehicle owner.
Arnold, MD
STEERING
Got error message that said "Forward Smart City Brake Support Malfunction" slso fot "smart brake malfunction" while driving. The ac stopped, the car speedometer kept going from 50 to zero. The car died and couldn't open doors, windows. Lost steering while driving. We were able to get off road and restart and fine for 2 weeks. While at still light tonight, the car turned off. Windows were up, couldn't open door, emergency blinkers would not come on. This is very dangerous.
NHTSA complaint #11753644 — an unverified report by a vehicle owner.
Arnold, MD
SUSPENSION
Got error message that said "Forward Smart City Brake Support Malfunction" slso fot "smart brake malfunction" while driving. The ac stopped, the car speedometer kept going from 50 to zero. The car died and couldn't open doors, windows. Lost steering while driving. We were able to get off road and restart and fine for 2 weeks. While at still light tonight, the car turned off. Windows were up, couldn't open door, emergency blinkers would not come on. This is very dangerous.
NHTSA complaint #11753644 — an unverified report by a vehicle owner.
Pittsburg, CA
ENGINE
Crack in Cylinder Head of engine. Mazda has been sued about this and have issued recalls on turbo engines, but not on non turbo ones though its the same systemic design issue with these engines. Wants me to pay 5-7k out of pocket.
NHTSA complaint #11734993 — an unverified report by a vehicle owner.
Lakewood, NJ
ENGINE
My cylinder head is leaking coolant. There is a well known and well documented issue with these cylinder heads cracking due to poor casting. This has become such a big issue that Mazda has even recalled the cylinder heads, BUT, only if the engine is equipped with Turbo. However, this issue is becoming enormous even for non turbo owners and is a huge safety issue as it can lead to overheating, stalling, and further damage to other components. I feel very strongly that it is time for Mazda to take some responsibility and extend the cylinder head recall to the non turbo engines.
NHTSA complaint #11733118 — an unverified report by a vehicle owner.
Fountain Valley, CA
ENGINE
Car had a coolant leak due to cracked cylinder head that was defective from the factory it was fixed but now the car has engine problems again. Don’t want to keep having these issues in the future
NHTSA complaint #11729758 — an unverified report by a vehicle owner.
Plainfield, IL
POWER TRAIN
System Failure: The Power Train (6-speed Automatic Transmission) suffered a major malfunction, documented by diagnostic codes P0731 (Gear 1 Incorrect Ratio) and P0780 (Shift Error). The vehicle is available for inspection. Safety Risk: The failure caused a sudden loss of propulsion while attempting to accelerate. This created an immediate risk of a rear-end collision and left the vehicle unresponsive in the path of oncoming traffic. The transmission's unpredictable shifting makes the vehicle unsafe to operate. Confirmation: The failure and the P0731 code were officially confirmed by Castle Mazda on March 2, 2026. The manufacturer (Mazda) has been notified but has denied a remedy, despite TSB MC-10160555-0001 addressing this specific internal defect. Warning Symptoms: There was no Check Engine Light or dashboard warning prior to or during the failure. The only warning was an extreme, abnormal mechanical grinding/clunking noise from the transmission. The lack of a malfunction indicator light (MIL) meant I had no electronic warning of a looming mechanical failure while in motion.
NHTSA complaint #11728615 — an unverified report by a vehicle owner.
Exton, PA
ENGINE
Per Mazda inspection, the back side of cylinder head #3 has an oil leak which is leaking onto the exhaust manifold. This creates a direct fire hazard as Mazda said they highly recommend not driving it for that reason. The Mazda dealership inspected and confirmed the issue, it in February 2026, with only 74,000 miles on the vehicle.
NHTSA complaint #11719756 — an unverified report by a vehicle owner.
North Charleston, SC
POWER TRAIN
I recently discovered a significant oil leak near the exhaust manifold of my 2018 Mazda 6 (2.5L NA), which has resulted in visible smoke and a burning oil odor. Upon taking the vehicle to the nearest Mazda dealership for a diagnosis, the service department informed me that the vehicle has suffered a cracked cylinder head. An active oil drip is visible behind the engine near the exhaust manifold immediately upon starting the car; consequently, the engine is leaking oil directly onto the exhaust components. This condition not only renders the vehicle inoperable but also presents a significant safety and fire hazard. At the time of this writing, my vehicle has only 46,996 miles and has been meticulously maintained. This mileage is well under the 60,000-mile powertrain threshold and represents a premature failure of a major internal engine component. There are numerous reports on Mazda owner forums describing this identical issue occurring in Mazda 6, CX-5, and CX-9 models. Some owners have even reported instances of minor fires or active burning under the hood due to oil contacting hot engine components. Mazda released Technical Service Bulletin TSB #MC-10241612-0001 (SA-037-23), which includes a redesigned cylinder head for 2018–2020 Mazda 6, 2019 CX-5, and 2016–2020 CX-9 models, demonstrating Mazda’s awareness of this design flaw. While the TSB currently only specifies the 2.5L Turbo engines and not the naturally aspirated variants, there is substantial evidence that this is a widespread defect across these model years, unrelated to owner misuse or vehicle mileage. Mazda should take full responsibility by issuing a formal recall or providing an extended warranty to cover naturally aspirated engines, thereby addressing this problem and preventing further safety risks.
NHTSA complaint #11709431 — an unverified report by a vehicle owner.
North Charleston, SC
ENGINE
I recently discovered a significant oil leak near the exhaust manifold of my 2018 Mazda 6 (2.5L NA), which has resulted in visible smoke and a burning oil odor. Upon taking the vehicle to the nearest Mazda dealership for a diagnosis, the service department informed me that the vehicle has suffered a cracked cylinder head. An active oil drip is visible behind the engine near the exhaust manifold immediately upon starting the car; consequently, the engine is leaking oil directly onto the exhaust components. This condition not only renders the vehicle inoperable but also presents a significant safety and fire hazard. At the time of this writing, my vehicle has only 46,996 miles and has been meticulously maintained. This mileage is well under the 60,000-mile powertrain threshold and represents a premature failure of a major internal engine component. There are numerous reports on Mazda owner forums describing this identical issue occurring in Mazda 6, CX-5, and CX-9 models. Some owners have even reported instances of minor fires or active burning under the hood due to oil contacting hot engine components. Mazda released Technical Service Bulletin TSB #MC-10241612-0001 (SA-037-23), which includes a redesigned cylinder head for 2018–2020 Mazda 6, 2019 CX-5, and 2016–2020 CX-9 models, demonstrating Mazda’s awareness of this design flaw. While the TSB currently only specifies the 2.5L Turbo engines and not the naturally aspirated variants, there is substantial evidence that this is a widespread defect across these model years, unrelated to owner misuse or vehicle mileage. Mazda should take full responsibility by issuing a formal recall or providing an extended warranty to cover naturally aspirated engines, thereby addressing this problem and preventing further safety risks.
NHTSA complaint #11709431 — an unverified report by a vehicle owner.
Ontario, OH
ENGINE
Cracked cylinder head causing oil leak and possible coolant leak. This is a known issue with this year and model. Mazda is trying to suggest the issue is only for the turbo engine, but the non-turbo engine is also defective, per countless reports online. I have a video from the service technician from the mazda dealership, but it is too big to upload.
NHTSA complaint #11694210 — an unverified report by a vehicle owner.
Fresno, CA
POWER TRAIN
Was driving then car suddenly shut down and all panel lights turned on. The car would not start after an hour it started but was Perkins when driving. Mechanics were unable to diagnose the issue.
NHTSA complaint #11688263 — an unverified report by a vehicle owner.
Oregon City, OR
SERVICE BRAKES
Premature caliper failure on front and rear. Ruined rotors at 40k miles, confirmed caliper failure by two service shops. Grinding/squeaking sounds intermittently been happening for since 30,000 miles
NHTSA complaint #11663276 — an unverified report by a vehicle owner.
at 75,000 milesProvincetown, MA
FUEL SYSTEM, GASOLINE:DELIVERY:FUEL PUMP
The contact owns a 2018 Mazda Mazda6. The contact stated upon taken the vehicle to the dealer for an oil change, the dealer notified the contact of a fuel leak. The dealer diagnosed the vehicle and informed the contact that the top of the fuel tank and bolts connected to the fuel pump were significantly rusted, causing the fuel leak. The dealer determined that the fuel tank and the fuel pump needed to be replaced. The vehicle was repaired. The manufacturer was notified of the failure and informed the contact that no assistance would be provided because the contact had already authorized the dealer to repair the vehicle. The failure mileage was approximately 75,000.
NHTSA complaint #11660947 — an unverified report by a vehicle owner.
Snellville, GA
ENGINE
Bought used with 47k miles. Two weeks later, took it to my mechanic for an inspection, they found a massive oil leak on the back of the motor. Took it back to the dealership and they diagnosed it as a cracked cylinder head, for which there is a known TSB and warranty extension. Unfortunately, the warranty extension only covers a coolant leak from the cracked cylinder head, not an oil leak. Thankfully, the dealership took care of me but had they not, I was looking at a $7k+ repair on a car I had owned for 2 weeks. In the TSB, Mazda acknowledges that there were both design and manufacturing flaws for the affected model years. In acknowledging the issue, they should have issued a recall for affected vehicles, not a simple warranty extension
NHTSA complaint #11659983 — an unverified report by a vehicle owner.
Cary, NC
SERVICE BRAKES
I am having my brake pads changed at a local mechanic and when changing the pads, the mechanic was unable to change them because the rotors and calipers were rusted and the brake pistons stuck. The previous recall only considered Mazda 6 up to 2013 but my 2018 has had the same problem.
NHTSA complaint #11646848 — an unverified report by a vehicle owner.
Rocklin, CA
UNKNOWN OR OTHER
Software error/loss of engine power. No warning of this before it happens. The car completely loses power, and stalls or stops in the middle of me driving. This has happened on the freeway and risked my life as well as my husbands, and children. This same issue has been a previous recall and fixed in 2019 for my car, and now it is happening again.
NHTSA complaint #11636672 — an unverified report by a vehicle owner.
Benton, KY
UNKNOWN OR OTHER
Coolant leaks at the cylinder head around the exhaust manifold causing my car to over heat. Also when my thermostat is set to the exact temperature for both sides my driver side blows cold and the passenger side blows hot
NHTSA complaint #11634788 — an unverified report by a vehicle owner.
Benton, KY
ENGINE
Coolant leaks at the cylinder head around the exhaust manifold causing my car to over heat. Also when my thermostat is set to the exact temperature for both sides my driver side blows cold and the passenger side blows hot
NHTSA complaint #11634788 — an unverified report by a vehicle owner.
Lafayette, NJ
ENGINE
Driving in traffic and the engine temperature warning appeared on dash. Dealer has confirmed there is a large coolant leak from the cylinder head. Mazda released a technical service bulletin regarding the issue affecting Mazda6, cx-5 and cx-9, but I will have to pay for a head gasket replacement.
NHTSA complaint #11634029 — an unverified report by a vehicle owner.
Harvey Cedars, NJ
ENGINE
Cracked cylinder head near the exhaust manifold. Created a large oil leak. Oil on the exhaust is a fire hazard. After one quart of oil loss a low oil level light comes on. This is a reported problem. One version of the engine I have has a Mazda TSB and an extended warranty. TSB 01-0022/23 A local repair shop has diagnosed the problem.
NHTSA complaint #11627463 — an unverified report by a vehicle owner.
Denver, CO
UNKNOWN OR OTHER
My car has stalled out on me 6 times in traffic and wouldn’t restart for hours. I took it to the Mazda dealership and they told me nothing was wrong but it continues to happen. I need something done as soon as possible
NHTSA complaint #11616978 — an unverified report by a vehicle owner.
Denver, CO
ENGINE
My car has stalled out on me 6 times in traffic and wouldn’t restart for hours. I took it to the Mazda dealership and they told me nothing was wrong but it continues to happen. I need something done as soon as possible
NHTSA complaint #11616978 — an unverified report by a vehicle owner.
Denver, CO
FUEL/PROPULSION SYSTEM
My car has stalled out on me 6 times in traffic and wouldn’t restart for hours. I took it to the Mazda dealership and they told me nothing was wrong but it continues to happen. I need something done as soon as possible
NHTSA complaint #11616978 — an unverified report by a vehicle owner.