2018 Mazda CX-5: excessive oil consumption

Filed Nov 9, 2026 · Engine · IL

On XXX, I was driving my 2018 Mazda CX-5 (SKYACTIV-G 2.5 non-turbo with cylinder deactivation, 67,000 miles) on [XXX] in [XXX], on the way to a work conference. Shortly after I got off the highway, smoke suddenly started filling the cabin. I could smell burning oil, and I honestly thought the vehicle was about to burst into flames with me inside it. I did not know what to do, and could barely breathe and see out the windows, i turned the fans on and lowered my windows to try and see out. I was still in traffic trying to find a safe place to stop, and I debated going through red lights just to get off the road. Sitting at a light in a car filling with smoke felt more dangerous than the intersection. No driver should ever have to make that choice. When I pulled over and opened the hood, smoke was pouring from the back of the engine near the firewall, and oil was seen seeping from the back of the engine onto the ground. There was no warning light or other warning before this happened. [XXX] Mazda diagnosed a cracked cylinder head a few hours after I had the vehicle towed from a parking lot next to the highway with leaking oil onto the exhaust manifold. The vehicle has been maintained mostly at Mazda dealers, and this was not wear or neglect. The repair cost was estimated at $5,200. Oil leaking onto a hot exhaust is a fire hazard, and in my case it filled the passenger cabin with smoke while I was driving. Mazda has issued a service alert establishing a replacement cylinder head for this engine, with oil leaks listed as a symptom. Mazda also extended coverage to 10 years or 120,000 miles for cracked cylinder heads on the turbo version of this engine (CSP11). There is no recall or extension for the non-turbo engine, even though this failure creates a smoke and fire risk while driving. I am asking the federal safety agency to investigate cylinder head cracking on 2018 and newer Mazda vehicles with the SKYACTIV-G 2.5 engine with cylinder deactivation. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 5

Filed Oct 28, 2026 · Engine · WA

My 2018 Mazda CX-5 Touring (2.5L non-turbo engine with cylinder deactivation) developed a burning oil smell that steadily worsened over several days. On XXX, at about 61,300 miles, I saw smoke coming from the engine compartment after driving. The engine had not overheated, and the car was regularly maintained. On XXX, an independent repair shop (A&M Auto Repair, [XXX] a large active oil leak. After steam cleaning the engine and removing the exhaust manifold, they found engine oil leaking from a hairline crack in the cylinder head, directly onto the hot exhaust manifold. The engine was also about one quart low on oil. The shop recommended replacing the cylinder head assembly, at a cost of about $5,700 before tax. Oil leaking onto the exhaust manifold is a fire hazard, and the smoke could reduce visibility for other drivers. Many other owners of 2018–2020 CX-5s with this engine have reported the same cracked cylinder head failure. I contacted Mazda Customer Experience (case number XXX) to request assistance. Mazda declined because the repair was diagnosed and performed by an independent shop rather than a Mazda dealer. I'm submitting this complaint so the federal safety agency can evaluate whether this cylinder head failure is a safety defect that warrants a recall. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Filed Oct 8, 2026 · Engine · WA

Cracked cylinder head- factory defect, causing oil to leak onto exhaust manifold. Smoke fills engine bay and cab through air vents, very high concern of engine bay fire. 2018 Mazda cx5 non turbo 2.5 sky active engine. Mazda knows of this defect and will not proved remedy.

Filed Sep 24, 2026 · Engine · NJ

2018 Mazda CX-5 2.5L NA Engine Cracked cylinder head and blown head gasket with leaking oil onto exhaust manifold resulting in white smoke & burning oil smell. No engine light. Issue confirmed by dealer and independent shop. Commonly reported issue amongst 2018-2021 Mazda CX-5 owners either naturally aspirated engines.

Filed Apr 13, 2026 · Engine · VA

The head gasket on the engine is cracked and is leaking oil and causing the oil to burn when car is driven. The problem was identified by a local mazda dealership and it is a well documented and known issue among SkyActive non-turbo engines. There were no warning lights or messages on the car, other than the smell of burning oil and smoke coming from the engine after driving. I have a toddler and the smoke and burning smell coming into my car every time I drive is concerning to our health. Mazda is well aware that the cracked head gasket issue extends beyond their turbo engines but did not include the non turbo engines in their extended warranty.

Filed Mar 30, 2026 · Engine · CT

Vehicle Information Year/Make/Model: 2018 Mazda CX-5 Engine: 2.5L Mileage at Failure: Approximately 115,000 miles Component: Engine Complaint Summary: I am reporting a sudden and unsafe engine failure involving a cracked cylinder head in my 2018 Mazda CX-5. This failure occurred without warning at approximately 115,000 miles and resulted in significant oil leakage from the engine. Description of the Failure and Safety Risk: While operating the vehicle, I detected a strong burning oil odor followed by visible smoke coming from the engine compartment. Upon inspection, it was determined that the cylinder head had cracked, allowing engine oil to leak onto hot engine and exhaust components. This condition presents a serious safety hazard, including the risk of fire due to oil contacting high-temperature surfaces. Notably, there were no warning lights, messages, or prior indicators of any issue before the failure occurred. The vehicle has been properly maintained and has not experienced overheating or misuse that would reasonably lead to this type of failure. Repair Information: The vehicle was diagnosed by an authorized Mazda dealership, which confirmed a cracked cylinder head. The estimated cost of repair is approximately $5,130. Additional Information / Defect Pattern: Through independent research, I have identified multiple reports of similar failures involving Mazda 2.5L engines in comparable vehicles. These reports describe nearly identical symptoms, including sudden oil leakage, smoke, and cracked cylinder heads at relatively low mileage. This pattern suggests a potential manufacturing or material defect rather than normal wear and tear. Manufacturer Response: I have contacted Mazda Customer Experience and escalated the matter. Mazda has declined to provide any assistance, citing the vehicle being out of warranty, despite the nature of the failure and associated safety concerns. Summary: This issue involves a critical engine component failure that can le

Filed Mar 18, 2026 · Engine · FL

My 2018 Mazda CX-5 AWD (2.5L SKYACTIV-G, non-turbo) was diagnosed by a Mazda dealer with a cracked/leaking cylinder head, a known manufacturing defect in the casting of the aluminum cylinder head. Engine oil is leaking from the rear of the cylinder head onto the exhaust manifold, creating a burning oil smell and visible oil accumulation at the rear of the engine. This is a documented fire hazard. The Mazda dealer confirmed the diagnosis matches Technical Service Bulletin SA-031-21, which Mazda issued in May 2021 specifically for this defective cylinder head design on 2018–2019 CX-5 models. The dealer additionally informed me that Mazda has internally acknowledged this as a growing, widespread problem across the 2018–2021 CX-5 model years, and that a recall may be forthcoming. Mazda customer service denied my goodwill repair claim despite acknowledging the TSB. The estimated repair cost is $7,000. The vehicle is currently not being driven due to the fire risk of oil contacting the exhaust manifold. This defect appears to affect a significant number of 2018–2021 Mazda CX-5 vehicles. I am requesting the federal safety agency open a formal safety defect investigation and compel Mazda to issue a recall. Multiple other owners have reported the same issue on the federal safety agency and in owner forums. This is a manufacturing defect not normal wear and tear and poses a serious fire safety risk to consumers.

Filed Mar 7, 2026 · Engine · KY

Vehicle developed burning oil smell. Dealership diagnosed a cracked cylinder head. No warning lights (yet. Eventually low oil pressure light would come on.) Potential for engine to lock up and lose power while driving putting occupants and others at risk. Know problem for 2018-2021 model years. Car no longer under warranty. Cost to repair $7,100. Technical Service Bulletin SA-031-21 issued regarding this problem.

Filed Mar 7, 2026 · Transmission · WA

2018 Mazda CX-5, 58,182 miles. Report date is 3/7/2026, low mileage for it's age. Vehicle has been exclusively purchased and serviced at the same authorized Mazda dealership for the lifetime of the vehicle, with all maintenance records on file. I began experiencing a strong burning oil smell inside the passenger cabin while driving. The fumes were noticeable to both the driver and passengers, creating a potential carbon monoxide/combustion fume exposure hazard that posed a safety risk to all occupants. Upon bringing the vehicle to the dealership, the technician diagnosed a cracked cylinder head requiring full replacement. This is a significant structural engine defect. Despite the vehicle being dealer-serviced its entire life, the repair cost was initially placed entirely on the owner. Mazda eventually provided partial financial consideration, though the root cause of why a cylinder head cracked on a well-maintained 58,182-mile vehicle was never adequately explained. I am filing this complaint because fumes entering the passenger cabin represent a serious safety defect, and I believe this issue may affect other 2018 CX-5 owners.

Filed Feb 18, 2026 · Engine · IL

Noticed the smell of burning oil and smoke from the engine while driving on the interstate with my husband and young children in the vehicle. Pulled over at a gas station to inspect and discovered large amounts of oil leaking. While at the gas station the low oil indicator came on. There were no warning or check engine lights prior to the incident. The dealership diagnosed cracked cylinder head. This was an extensive and costly repair. I have now learned that Mazda is aware of how common this issue is with this year/make/model. This should be a covered repair or recalled part.

Filed Nov 3, 2025 · Engine, Transmission · NC

2018 Mazda CX-5, 2.5L NA Has been diagnosed with leak in the cylinder head cover, which has resulted in engine oil leaking directly onto the exhaust manifold. This leak produces significant smoke and a strong burning oil smell while the vehicle is running. There are numerous reports on Mazda owner forums describing the same issue occurring in Mazda CX-5 models. Some owners even reported instances of minor fires or active burning under the hood due to oil contacting hot components. Mazda released Technical Service Bulletin TSB #SA-031-21, which includes a redesigned cylinder head for the 2018–2019 CX-5 models. This bulletin demonstrates Mazda’s awareness of the design flaw. The TSB only covers turbo 2.5L engines and not normally aspirated engines. There is substantial evidence that this is a widespread defect in 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 address the problem and prevent safety risks.

Filed Oct 20, 2025 · Engine · 59,000 miles · NY

The contact owns a 2018 Mazda CX-5. The contact stated that while driving at 45 MPH, there was smoke coming from the engine, and the contact smelled an oil-burning odor. No warning lights were illuminated. A dealer was contacted. The vehicle was towed to the dealer where it was diagnosed and determined that the cylinder head was damaged, causing oil to leak into the cylinders, and that the engine needed to be replaced. The manufacturer was notified of the failure, and promised to open a case and give the contact a callback within 24 to 48 hours. The approximate failure mileage was 59,000.