2018 Mazda CX-5 Engine Problems

2018 CX-5, VIN [XXX] , 60,182 miles. Skyactiv-G 2.5L with cylinder deactivation (VIN 8th digit M). Head gasket leak diagnosed by independent mechanic and confirmed by Mazda dealer, who referenced Service Action SA-073/24. Oil actively leaking onto garage floor and contacting exhaust manifold, causing burning smell and potential fire risk. Defect was first documented by dealer at 52,966 miles within powertrain warranty. This is a known manufacturing defect affecting the cylinder head casting on 2018+ CX-5 models with cylinder deactivation INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

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.

My 2018 Mazda CX-5 with 81,000 miles and an up to date maintenance record started leaking oil after an oil change. It started to notice smoke coming from under the hood and a puddle of oil in my garage floor. I took it to the shop where they determined it was a cracked cylinder head. I purchased this vehicle new from the dealership, and I have taken really good care of it. They need to issue a recall because it is a very expensive repair. Shame on you Mazda!!

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.

cracked cylinder head at 109521miles, no warning, no temp gage no light indicators came on. I have pictures of vehicle dashboard showing no warning as it is smoking going to Mazda dealership. Dealership advised me of this being an issue in my make and model> I also have video from dealership. I have reached out to Mazda several times, its going on 5 weeks and I am getting the run around. Please let me know what other information is needed.

Cracked cylinder head confirmed by Mazda Dealership. No warning lights or indicators. We noticed white smoke and a burnt plastic smell after a drive one night. Dealership confirmed oil was leaking onto the exhaust, a potential fire hazard.

I started observing oil leaks and took it to the dealership. They changed the gasket for 2500$ and the oil leak worsened. Dealer is asking for $4500 to replace a bad cylinder head. I am told that this is a common Mazda manufacturing defect and Mazda denied the repair cost coverage request. Any help would be really appreciated. This is commonly reported Mazda issue and especially on a low mileage vehicle woth 56000 miles on, this is not fulfilling the promise of quality machinery.

Oil leak from defective head that occurred behind exhaust manifold leaking hot oil onto the hot exhaust causing the potential for fire. Leak started at 44,000 miles. This manufacture defect is not being covered by Mazda or a recall even though the high potential of fire and serious injury.

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

I am reporting a safety issue involving engine failure and fumes entering the vehicle cabin as well as unintended braking post major engine repair at 75,000 miles on my 2018 Mazda CX5. My vehicle developed engine problems consistent with a cylinder head/coolant defect and began allowing fumes/smoke to enter the cabin while driving. This created a health and safety concern for occupants. I reported this to the dealership and was told the vehicle was safe to drive despite the presence of fumes in the cabin. A major engine repair was later performed. A few days following the repair, additional warning lights and system malfunctions appeared, including brake system warnings, and the vehicle later braked unexpectedly while driving nearly causing me to be rear-ended. The vehicle has been inspected by the dealership, but the root cause of the fumes and subsequent safety issues has not been clearly explained. This situation created a safety risk due to exposure to fumes inside the cabin and unexpected vehicle behavior while driving. Smoke/fumes video and any additional documentation can be provided upon request. Attaching the costly invoice as well.

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 NHTSA open a formal safety defect investigation and compel Mazda to issue a recall. Multiple other owners have reported the same issue on NHTSA and in owner forums. This is a manufacturing defect not normal wear and tear and poses a serious fire safety risk to consumers.

All of a sudden, my engine started making this ticking noise. I brought it to a mechanic, and he said the noise is coming from inside the engine. He checked for codes and everything, but nothing came up. The only way to look at it is to take the engine apart from what he told me. I started researching for solutions online before doing this and I came across other Mazda CX5 owners complaining of the same thing. I listened to a few of these videos of the sound it makes and sounds just like my car. Apparently, it is a common issue connected with the Hydraulic Lash Adjusters, and I am amazed that Mazda has not reached out to people affected by this. I am not sure what the long-term issue is with this noise, but it can't be good if it's in the engine. Who knows what kind of damage it could cause.

Turned car on when leaving for work. Smelled a strong burning smell. Fluid all under car on the driveway. Took the vehicle to repair shop and they stated that it was the cylinder head and that there was a possible recall or warranty extension for this particular issue. I called Mazda and they said it was an issue but for the 2019 model and not the 2018. After doing some research I have read where this issue seems to be happening for the 2018 as well and they are not taking responsibility for it.

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.

While driving, my 2018 Mazda CX-5 experienced a sudden and complete loss of engine power without warning. The engine shut down while the vehicle was in motion; however, electrical systems such as the radio, heat, and electronics remained operational. The vehicle lost propulsion, creating a serious safety risk in traffic. The vehicle had recently been serviced at an authorized Mazda dealer for completion of PCM and fuel-system recalls. Shortly after recall service, the engine failure occurred. No warning lights or prior symptoms were present. An independent mechanic suggested possible engine seizure, but a full diagnostic evaluation (including compression testing or internal inspection) has not been completed. The cause of the sudden power loss remains undetermined. This incident represents a potential safety defect involving unexpected engine shutdown and loss of propulsion.

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.

Hydraulic lifters keep having issues

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.

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.