This SA supersedes the previously issued SA(s) listed below. The changes are noted in Red. SA-061/25 12/17/25 DESCRIPTION If you encounter any type of electrical concern (e.g, dead battery, engine no start, DTC(s) stored...), interview the customer before proceeding with normal MGSS diagnosis by asking if any aftermarket devices have been installed. Aftermarket devices may be the cause of the electrical concern. Below are a few examples of unusual electrical concerns caused by aftermarket devices. Examples: 1. Devices connected to the DLC-2 (battery discharge/DTC stored) 2. Devices plugged into the 12V outlet 3. GPS tracking device (engine no start/battery discharge) 4. Dash cam (DTC stored)
full bulletin at NHTSA ↗2021 Mazda Mazda6 engine problems
moderate Owners of the 2021 Mazda Mazda6 have filed 12 NHTSA complaints about the engine at roughly $3,100 to repair (U.S. federal records, as of July 2026). Source: NHTSA Office of Defects Investigation. See engine across all vehicles →
Complaints
12
Recalls
0
Avg fix
$3,100
| Model year | engine complaints |
|---|---|
| 2017 Mazda6 | 3 |
| 2018 Mazda6 | 21 |
| 2021 Mazda6 (this page) | 12 |
Is there a fix? Manufacturer service bulletins
The manufacturer has issued service bulletins covering engine 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.
This bulletin supersedes the previously issued bulletin(s) listed below. The changes are noted in Red. 09-012/21 12/13/21, 06/10/21 and 04/27/21 DESCRIPTION Some customers may experience all of following symptoms: The door lock/unlock operation will not work using the remote transmitter button. 1. The door lock/unlock operation will not work using the door lock/release touch sensor. 2. The engine will not start using the ignition switch. 3. The transmitter operates by itself. 4. The key battery drains faster than usual. 5. Symptoms 1-3: This may be caused when excess load is applied to the remote transmitter, deforming the electrical terminals and creating poor contact with the battery. To e
full bulletin at NHTSA ↗Valve Stem Seals Class Action Settlement Program for Excessive Oil Consumption and Oil Consumption Powertrain Warranty Extension Special Service Program SSPD5. Updated April 28, 2026 – Related oil part number for warranty claims is now 0000-77-5W30-QT (engine oil) as the 5555 warranty part number has been removed. As a reminder, all coverage reverts back to the original extension of 7 years or 84,000 miles whichever comes first. WARRANTY EXTENSION If you have any questions regarding this campaign, please read the Mazda Dealer FAQ’s available in MGSS under this campaign before contacting Dealer Recall Help. Effective October 25,2025: In the final settlement agreement, which was approved by th
full bulletin at NHTSA ↗This Service Alert supersedes the previously issued SA listed below: The changes are noted in Red. SA-011/24 02/12/24, 06/06/24, 07/29/24 DESCRIPTION Mazda has developed factory recommended scheduled maintenance services that support all major vehicle systems. Mazda recommends dealers follow the scheduled maintenance tables as cited in the vehicle-specific workshop manual or owner's manual. Services performed outside of Mazda's factory scheduled maintenance are not recommended. These services are unnecessary and create unneeded expenses for your customers. SCHEDULED MAINTENANCE Refer to the applicable Workshop Manual or Owner's Manual for vehicle -specific manufacturer scheduled maintenance.
full bulletin at NHTSA ↗This Service Alert supersedes the previously issued M-Tip(s) listed below. The changes are noted in Red text. MT-002/19 09/30/19 and 12/19/19 DESCRIPTION If an engine assembly is replaced after a catastrophic internal mechanical failure, clean the intake manifold internally before installing a replacement engine assembly. If the intake manifold is not cleaned properly, the replacement engine may fail prematurely. Metallic debris from the old engine (with catastrophic internal mechanical failure) may rest inside the intake manifold. When the new engine assembly is installed, debris in the intake manifold will be ingested into the new engine and cause internal damage. Clean the intake manifold
full bulletin at NHTSA ↗Source: NHTSA manufacturer communications. Bring the bulletin number to your dealer or shop.
The failure pattern owners describe
Owners consistently describe low oil warning lights appearing between scheduled oil changes starting as early as 3,500 miles, with some vehicles requiring top-offs every 1,000–3,700 miles. One owner calculated roughly 1 quart consumed per 3,000 miles, and rates increasing as mileage climbs. Manual dipstick checks confirm actual oil loss; owners find no visible external leaks underneath. All 12 narratives point to the same failure: defective valve stem or valve guide seals, allowing oil to escape into the combustion chamber and exhaust. Mazda issued TSB-01-012/21 acknowledging the defect and has confirmed certain VINs fall within the affected range. However, owners report Mazda offers no permanent repair—only refilling oil at service visits. Multiple owners express concern that continued operation under low-oil conditions risks engine damage, seizure, or sudden power loss. The issue affects brand-new vehicles and appears unresolved even after purchase, leaving owners to manage the problem through frequent manual top-offs during the warranty period.
Same Mazda Mazda6 engine reports on nearby years: 2018
Failure modes owners describe
Excessive oil consumption (oil burning)
Engine burns oil at an abnormal rate, causing the low oil warning light to illuminate well before the scheduled service interval. Owners report the vehicle consumes roughly 1 quart per 3,000 miles or faster. Root cause identified in multiple narratives as defective valve stem seals or valve guide seals allowing oil to enter the combustion chamber.
When: Starts between 3,500 and 17,000 miles; one owner noted consumption increasing at 12,700 miles
Symptoms owners cite: Low oil pressure warning light illuminates between oil changes; Manual dipstick checks confirm oil level drops below normal; No visible external oil leaks; Oil warning recurs within 1,000-3,700 miles after topping off
Repairs/costs cited: Mazda has no confirmed repair available; dealership response is to refill oil only. Some owners report Mazda states the problem cannot be fixed.
Recalls/TSBs owners mention: TSB-01-012/21 issued acknowledging the defect. Mazda acknowledged defect but offers only refill service, no permanent fix per owners.
Synthesized from 12 NHTSA owner complaints — unverified consumer allegations, summarized for patterns. The verbatim filings appear below.
What owners are reporting 12 most recent
Engine oil low warning 2k miles after oil change and again a week after topping oil off.
The contact owns a 2021 Mazda Mazda6. The contact stated that the oil light continually illuminated on the instrument panel while driving at various speeds. The contact had taken the vehicle to the dealer where he was informed that the vehicle was consuming an excessive amount of oil. Upon investigation, the contact discovered information that a defective valve in the engine might have been the…
Vehicle displays low engine oil light about every 1,000 miles due to burning oil from faulty valve stem seals from factory assembly. Mazda has acknowledged the defect but plans to only refill engine oil. The defect could lead to possible injury due to low oil which could cause the engine to seize and cause sudden loss of power.
The engine oil low light has illuminated multiple times. I verified that there is no external engine oil leak. I have added oil and driven it for a couple thousand miles and the light is now on again. The car is brand new and should not be burning oil. Its a known issue as Mazda has a service bulletin but no fix for it. This is the bulletin number TSB-01-012/21.
Excessive oil consumption. Recently purchased new vehicle with 0 miles. Oil low level warning light on at 3500 miles. Manually checked oil level. Added one quart. Online research indicates problem is created by faulty valve guide seals which allows oil into the engine combustion chamber and exhaust. Vehicle will be taken to dealership for inspection.
The low oil pressure light had turned on shortly after my first oil change (roughly at around 6k miles). I had the service done at a trusted service shop back in April 2021. I wrote it off mentally thinking that it was just a one off thing and that the shop may have made a mistake and underfilled the engine because of unclear specifications between the mazda6 Turbo version vs other models within…
Low engine oil light came on at around 13,700. Last oil change was at 10,000 miles. Checked oil dipstick, oil level slightly below first marker hole.
My car displayed a low oil level light between oil changes and after checking the dipstick it was low. No sign of visible oil leak so upon further research I was made aware of a TSB about defective valve seals causing excessive oil consumption. My cars VIN is in the affected range outlined in the TSB. Now when I drive it's likely that slow but permanent damage could be occuring in my vehicle.
The issue I am experiencing is one that many are in regards to the oil consumption. My check oil light came on prematurely in regards to the recommended scheduling for these sorts of vehicles, at around 3500 miles approximately. This is a vehicle that experienced this issue under 10k miles.
Low oil light comes on. Using excessive oil between oil changes.
Had engine trouble with your 2021 Mazda Mazda6?
File a complaint with NHTSA → It's free, official, and how every report above got here — owner filings are the federal safety record this page is built on.
Common questions
How serious is the engine problem on the 2021 Mazda Mazda6?
It's a documented issue but not catastrophic. 12 complaints have been filed. Repairs average $3,100 and most owners catch it before it causes a breakdown.
At what mileage does the engine typically fail?
Mileage data is limited for this issue. Owners report failures across a wide range, suggesting cause is more about driving conditions and maintenance than mileage alone.
What does it cost to fix?
Independent shops typically charge around $3,100 for engine 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 engine?
No active recalls currently cover engine 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.
Related
Complaint and recall data sourced from the National Highway Traffic Safety Administration (NHTSA)
public records database. Verify the raw federal record at
nhtsa.gov/vehicle/2021/Mazda/Mazda6.
Severity ratings are derived from reported crashes, fires, injuries, and fatalities. Repair cost estimates are
independent-shop national averages and may differ in your area. Some links on this page are affiliate links.