2018 MAZDA CX-5 Complaints

Cracked cylinder head due to defect in the casting process. Oil leaking thru the crack landing on the exhaust manifold causing an odor and possibly toxic fumes in the cabin of the vehicle.

Mazda has inspected the car and determined that there is a crack in the cylinder head. This is apparently a known defect in 2018-2021 Mazdas with 2.5L engines, including, without limitation, the 2018 Mazda CX-5. The cracked cylinder head has caused leaking coolant, which can drain into the engine and create serious safety issues. Mazda is aware of the issue, however, they are claiming that it is not covered by warranty.

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.

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.

Driving fine at low speeds (under 40mph), once I accelerate to highway speeds the engine misfires, check engine light flashes, Smart City Brake System Malfunction, Radar Malfunction, and car losses all engine power. Car just coast, lights and brakes still work. Check engine code moves around and will be on cylinder 3 sometimes and cylinder 4 other times. Able to replicate this issue multiple times. Serious safety concern.

2018 Mazda CX-5, 2.5L Naturally Aspirated Engine The vehicle has been diagnosed with a leak from the cylinder head cover, resulting in engine oil dripping directly onto the exhaust manifold. This issue causes noticeable smoke and a strong burning oil odor inside the cabin while the engine is running. This defect presents multiple serious safety concerns: 1) Health hazard due to prolonged exposure to burning oil fumes inside the vehicle. 2) Fire risk from oil contacting hot engine components. 3) Potential engine failure, which could lead to vehicle stalling or loss of control, increasing the risk of a crash and possible loss of life. Mazda issued Technical Service Bulletin TSB #SA-031-21, which introduced a redesigned cylinder head for 2018–2019 CX-5 models. The release of this TSB indicates Mazda’s awareness of the underlying design flaw. There is substantial evidence, including numerous owner reports, that this is a widespread issue affecting these model years. The defect is not related to vehicle mileage or user negligence. Mazda should be held fully accountable and take corrective action by issuing a formal safety recall or offering an extended warranty to affected owners. Immediate attention to this matter is necessary to protect consumer safety and prevent future incidents.

Cracked cylinder head leaks oil directly onto hot exhaust, causing smoke, fumes in cabin and a fire risk.

the cylinder head has a crack in it witch sprays oil all over the engine.it also sprays oil on to the very catalitic converter that's very hot .smoke is everywhere and iam afraid it will cause a fire

Back up cameras fail infotainment system reboots and maps on the system inadvertently counts stops plus changes volume at loudspeaker telling me “this is the level “ and is on highest volume. Which you can’t turn down. All are dangerously interfering with driving. Please put pressure on Mazda to fix and not just update software when the problem has been fixed called CMU

I own a 2018 Mazda CX-5. I currently have 64,770 miles on the car. I have had a burning smell and smoke coming from the engine. The car was taken to the dealer (John Kennedy Mazda Conshohocken) and I was told it was fixed by replacing a gasket. The smell and smoke persisted. I took it back to the dealer and now I am told there is a leaking cylinder head. I do not feel safe driving this car especially with my kids in the car while the engine is smoking. I have had to pull over on the highway due to this. No warning lights were on until a week prior to taking it back a second time when my oil light finally came on.