What are the most common Mazda Mazda6 problems?
According to Au7o's analysis of 3,550+ owner reports, the 2018 Mazda Mazda6 has 8 documented issues. The most frequently reported are: Variable Valve Timing (VVT) Actuator Failure, Low-Pressure Fuel Pump Impeller Cracking / Engine Stall (Recall 21V875 / 5321K), SkyActiv-G 2.5T Turbo Cylinder Head Cracking / Coolant Leak. Of these, 3 are rated critical and should be addressed promptly.
Is the Mazda Mazda6 reliable?
The 2018 Mazda Mazda6 has 8 known issues documented across 3,550+ owner reports. 3 issues are rated critical: Variable Valve Timing (VVT) Actuator Failure and Low-Pressure Fuel Pump Impeller Cracking / Engine Stall (Recall 21V875 / 5321K) and SkyActiv-G 2.5T Turbo Cylinder Head Cracking / Coolant Leak. Prospective buyers should inspect for these issues and factor potential repair costs into their purchase decision. Regular maintenance following the manufacturer's schedule helps prevent many common problems.
How much does it cost to fix common Mazda Mazda6 problems?
Repair costs for known Mazda Mazda6 issues range from $200 to $6,000, depending on the specific problem and whether you choose DIY or professional repair. The most critical issue, Variable Valve Timing (VVT) Actuator Failure, typically costs $400-$1,200 to repair. Au7o provides step-by-step DIY maintenance guides that can help reduce repair costs.
What is the 2009-2021 Mazda Mazda6 Variable Valve Timing (VVT) Actuator Failure?
The exhaust-side VVT actuator (cam phaser) fails due to oil sludge and wear, causing timing codes and engine rattle. The actuator solenoid can also stick, leading to incorrect valve timing. Oil change neglect accelerates failure. Common on both MZR and early SkyActiv 2.5L engines… Repairs typically run $400-$1,200. Severity: high.
What is the 2018 Mazda Mazda6 Low-Pressure Fuel Pump Impeller Cracking / Engine Stall (Recall 21V875 / 5321K)?
Recall 5321K / NHTSA 21V875 covers certain 2018 Mazda6 vehicles built with the subject low-pressure fuel pump. An inadequately dense impeller can develop surface cracking, deform and interfere with the pump body, causing fuel-pump failure, no-start or an engine stall. Severity: high.
What is the 2018-2021 Mazda Mazda6 SkyActiv-G 2.5T Turbo Cylinder Head Cracking / Coolant Leak?
A proposed class action alleges that the turbocharged SKYACTIV-G 2.5T engine in 2018-2021 Mazda6 (and other Mazda models) has a structural weakness in the cylinder head near the exhaust manifold. Cracks can develop at the stud bolt hole or the outside of the exhaust manifold, all… Repairs typically run $2,000-$6,000. Severity: high.
What is the 2009-2021 Mazda Mazda6 Rear Brake Caliper Seizing?
Rear brake calipers seize due to corrosion of slide pins and the integrated parking brake mechanism. Salt-belt vehicles are especially affected. Causes dragging brakes, uneven pad wear, and premature rotor warping. The parking brake cable can also corrode and prevent full caliper… Repairs typically run $250-$650. Severity: medium.
What is the 2014-2021 Mazda Mazda6 Clutch Judder on SkyActiv Manual Transmission?
Manual transmission Mazda6 SkyActiv models experience clutch judder similar to the Mazda3 issue. The dual-mass flywheel and clutch disc friction material cause shuddering during engagement, especially from a stop. Mazda acknowledged the issue via technical service bulletin. Repairs typically run $900-$2,000. Severity: medium.
What is the 2014-2021 Mazda Mazda6 SkyActiv-G Intake Valve Carbon Buildup (Direct Injection)?
Because the SkyActiv-G direct-injection engine sprays fuel directly into the cylinder, no detergent fuel ever washes the back of the intake valves. Oil vapor drawn through the PCV system bakes onto the hot valve stems and accumulates as hard carbon, typically becoming noticeable… Repairs typically run $300-$600. Severity: medium.
What is the 2014-2021 Mazda Mazda6 Mazda Connect Infotainment Freezing / Reboot Loop?
Mazda communications document multiple distinct infotainment paths: 2014 navigation freezes, 2016 software-correctable black-screen/freezing/reboot concerns, a narrow 2016 CMU hardware shutdown, and diagnostic guidance through 2021. CSP13 provides a 24-month limited warranty exte… Severity: medium.
What is the 2014-2021 Mazda Mazda6 EGR Valve Carbon Buildup and Coolant Leak (SkyActiv 2.5L)?
The SkyActiv 2.5L engine in third-generation Mazda6 models uses a cooled EGR system that is prone to carbon buildup and coolant leaks. The EGR valve and cooler accumulate carbon deposits over time, restricting flow and causing rough idle and reduced performance. Additionally, the… Repairs typically run $200-$800. Severity: medium.
