Ethanol is becoming a common additive in gasoline. Gasoline containing ethanol is likely available at your local gasoline station. Typical blends of ethanol include E10 and E85. E10: A blend of 10% ethanol and 90% gasoline. E85: A blend of 85% ethanol and 15% gasoline All Mazda vehicles can run on gasoline containing up to 10% ethanol (E10) but only some 1999-2001 B3000 trucks can run on gasoline with more than 10% ethanol blended. E10 compatible vehicles: All Mazda vehicles. E85 compatible vehicles: 1999-2001 B3000 Mazda trucks with the 8th VIN digit is V.
full bulletin at NHTSA ↗2018 Mazda Mazda6 fuel system problems
moderate Owners of the 2018 Mazda Mazda6 have filed 3 NHTSA complaints about the fuel system at roughly $1,200 to repair (U.S. federal records, as of July 2026). Source: NHTSA Office of Defects Investigation. See fuel system across all vehicles →
Among the 5 model years of Mazda Mazda6 in our records for fuel system problems, this one ranks #2 by owner-complaint volume.
Is there a fix? Manufacturer service bulletins
The manufacturer has issued service bulletins covering fuel system on this vehicle — documented repair instructions, service campaigns, or warranty extensions sent to dealers. A TSB isn't a recall (it's not a free safety remedy), but it's the manufacturer acknowledging the issue and how to fix it.
In support of the new MRT distribution, Mazda will ship to dealers a new Dual Purpose Diagnostic Leak Detector beginning March, 2019. Training videos will be posted to MGSS shortly and Workshop Manual procedures will be revised gradually.
full bulletin at NHTSA ↗The SKYACTIV®-G 2.5T engine requires a unique oil filter (PY8W-14-302) which is NOT interchangeable with other SKYACTIV® oil filters. The unique oil filter can be identified with two white bands as shown below.
full bulletin at NHTSA ↗Some vehicles may experience a rough idle with the check engine light on and DTC P0015 / P0524 stored in memory. P0015:00 - Exhaust CMP timing over-retarded P0524:00 - Engine oil pressure too low This is caused by a drop in engine oil pressure due to a piece of foreign object stuck on the oil pump pressure relief valve or oil control valve (OCV). The temporary entry of the foreign object triggers a check engine light on, but rough idle will not be produced until a later time.
full bulletin at NHTSA ↗Source: NHTSA manufacturer communications. Bring the bulletin number to your dealer or shop.
What owners are reporting 0 most recent
Common questions
How serious is the fuel system problem on the 2018 Mazda Mazda6?
It's a documented issue but not catastrophic. 3 complaints have been filed. Repairs average $1,200 and most owners catch it before it causes a breakdown.
At what mileage does the fuel system typically fail?
Based on the 3 complaints filed, fuel system issues most often appear around 50,333 miles. Some report problems earlier; some make it well past 150,000 with no symptoms. Maintenance habits matter — vehicles that received timely fluid services and were not regularly overworked tend to last longer.
What does it cost to fix?
Independent shops typically charge around $1,200 for fuel system repairs on this vehicle. Dealer pricing tends to run 20-40% higher. The exact figure depends on the specific failure mode, parts availability, and your local labor rates. If you're outside factory warranty, an extended service contract often covers this category.
Are there any recalls related to fuel system?
No active recalls currently cover fuel system issues on this vehicle. The complaints filed represent owner-reported failures that haven't risen to the level of a manufacturer-issued recall — but they're still worth knowing about before you buy or budget for repairs.