What 113 owners told NHTSA about the 2018 Mazda Cx-50

The contact owns a 2018 Mazda CX-5. The contact stated that white smoke was coming from the engine compartment whenever the vehicle reached normal operating temperature. The contact stated that smoke entered the passenger’s side compartment through the air vents and was coming from underneath the hood. The contact stated that there was a burning odor coming from the engine compartment due to an oil leakage. The smoke impaired visibility while driving. The most recent failure had occurred while driving approximately 35 MPH on a city roadway. The vehicle was driven to an independent mechanic to be diagnosed, and then to the dealer for further inspection. The independent mechanic diagnosed the vehicle with a cracked cylinder head and recommended that the vehicle be taken to the dealer for additional diagnostic tests. The dealer diagnosed the cylinder head as porous and informed the contact that the cylinder head needed to be replaced. The manufacturer was notified and informed the contact that the repair would not be covered. The vehicle was not repaired. The contact stated that the failure had occurred intermittently and became more frequent and severe during hotter weather. The failure mileage was approximately 83,000.

NHTSA ODI 11747961

I am submitting this complaint regarding a cylinder head failure on my Mazda CX-5. The vehicle has approximately 53,000 miles and has been properly maintained throughout its service life. The vehicle developed a crack in the cylinder head, which was subsequently confirmed by an authorized Mazda dealership. Mazda has previously issued a Technical Service Bulletin (TSB) addressing cylinder head cracking on certain vehicles; however, my vehicle's VIN is not included in the covered range despite experiencing the same failure described in the TSB. The dealership initially provided a repair estimate of $8,789 plus tax to replace the cylinder head. Following further discussions, the dealership reduced the repair cost to $3,903 plus tax. They recognize that this crack is not part of normal wear and tear but due to the VIN number not being included in the recall are unable to provide full coverage. A cylinder head crack is a major engine failure that should not occur on a well-maintained vehicle with only 53,000 miles. I am concerned that vehicles outside the VIN range identified in Mazda's TSB may be experiencing the same defect and that the scope of the issue may be broader than currently recognized. The vehicle was purchased used from the same Mazda dealership that diagnosed the failure and is currently performing the repair evaluation. I respectfully request that NHTSA review this issue to determine whether additional Mazda CX-5 vehicles may be affected by the same cylinder head defect despite not being included in the existing TSB.

NHTSA ODI 11744861

I took my car to the dealership because it was leaking oil and coolant. Upon verification, I was informed that my vehicle had a cracked cylinder head. They told me that the repaired will cost me $5500. Unfortunately this is an amount that I do not have. So I reached out to the Mazda Corporate and they told me that there is no repair assistance can be provided and that I should reach out to Mazda Dealership and see if they may accept to put the cost of the repair towards the Good Will Repair. Unfortunately I haven’t been successful with that either. My Mazda Corporate case number is 00450563. This issue is created safety issue with burning engine oils and fume entering the vehicle. This is well known issue with this car model and unfortunately Mazda has made a recall on any of them. While I understand that this may cause Mazda Millions if a recall is put out, it will great to assist with the ones experiencing this issue. Any assistance regarding this matter will be truly appreciated.

NHTSA ODI 11738764

Like many other complaints. My 2018 Mazda cx5 GT is having the same issue with the cracked cylinder head. I only have about 36-38k mileage on it ( I forgot the exact). Mazda dealership will not cover the cost. NEVER had an accident to the front and only one accident to the back when I got rear ended in 2019. If this is a wide spread issue, why is this not a recall? and why is it only the turbo engine gets extended warranty? The repair cost right now approximately $9,500. I never do any maintenance at Mazda so I doubt they will give me the good will assistance but I am still waiting for an answer. I hope NHSTA will do something because this issue will continue with all other owners that have the same year model.

NHTSA ODI 11738405

We purchased this vehicle used from Mazda of Orange in July 2025 with 52,399 miles on it. After 6 months of ownership and approximately 3,000 miles there was a burning smell. We took it to our local mechanic and the following repairs were required: Replacement of cracked belts, Replacement of cracked axle boots, Replacement of an excessively loose front axle, Replacement of valve cover gasket. Cost was $3,000 and the dealer refused to reimburse us. Now the car is leaking oil and needs a new head gasket and cylinder head surface machined. Quote was approximately $3,500. We have requested Mazda perform this repair. Will you please look into these vehicles? These are significant defects on a car with such low miles. We also believe that some of these defects were know to the dealer but are unable to prove it. We believe our vehicle is part of a batch that has signficant mechanical defects. Current mileage of the vehicle is 56,865.

NHTSA ODI 11738202

another case of a 2018 cx-5 cracked cylinder head. 70k miles and regularly maintienced. no warning other than oil showing on the ground. took it in to mazda dealership and they came back after looking at it and declared it was a cracked cylinder head priced at 6.8k. after looking it up it appears to be a casting issue that has affected many mazdas but mazda corp. will not take fault.

NHTSA ODI 11735291

My CX-5 has 86,120 miles. I noticed a burnt oil smell coming into the car and later found oil droplets on my garage floor. I took it in to my neighborhood garage and they found an oil leak coming from the cylinder head. They recommended I take to my Mazda dealer. I had it towed to Pearson Mazda, Richmond,VA. They inspected it and stated I had a cracked cylinder head. I have a 100K extended warranty that will cover most of the cost to repair it. However, I found the Mazda CX-5 2018-2021 models have a cylinder head defect. I found a Mazda Service Alert, #SA-031/21 and on Reddit a Mazda CX-5 owners page that has many stories of the same problem, cracked cylinder head. Some have had Mazda cover the repair cost or given a major discount and provided an extended warranty after repair. I reviewed this with Pearson Mazda and they stated that my car does not fall in the vehicle numbers that they will cover. This is a known issue and they will not acknowledge it for my car. I have contacted Mazda Corporate and waiting for a callback. Litigation has been filed for the CX-5 Turbo customers and they have received restitution. This is also a major issue on non-Turbo customer’s SUVs. I have read that the 2018-2021 manufacturing (casting) of the cylinder head was defective. However, Mazda is not admitting it because a RECALL would cost them millions to fix the cylinder head issue on all the affected vehicles. But, they are at fault and should work with all customers that have been affected by this issue. Therefore, I am requesting NHTSA to make this a public safety matter and have Mazda be accountable for the issue. Thank you!

NHTSA ODI 11734839

My 2018 Mazda CX five experience catastrophic engine failure at approximately 119,000 miles despite proper maintenance. The failure resulted in a repair estimate exceeding $9500. This type of failure raises concerns regarding potential engine defects or premature mechanical breakdown. Mazda acknowledged the issue by offering a minimal Goodwill payments, but refused meaningful assistance. I am reporting the issue to determine whether similar failures are occurring with Mazda and further investigation is warranted.

NHTSA ODI 11734878

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)

NHTSA ODI 11733339

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.

NHTSA ODI 11731395

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.

NHTSA ODI 11730869

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.

NHTSA ODI 11730506

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.

NHTSA ODI 11730122

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.

NHTSA ODI 11730227

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!!

NHTSA ODI 11728174

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

NHTSA ODI 11727886

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.

NHTSA ODI 11725144

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.

NHTSA ODI 11722666

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.

NHTSA ODI 11722628

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.

NHTSA ODI 11719213

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.

NHTSA ODI 11718745

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.

NHTSA ODI 11716158

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.

NHTSA ODI 11714123

The infotainment system consistently changes stations and volume on its own. Knob will not allow you to make adjustments . Contacted dealer and infotainment Is not covered under warranty , or extended warranty. Now the collision notification is not working. Warnings from system that it has failed and causes system to not Register any movement . This has been going on recently. Now have to drive it as it doesn’t have the system. And have to use my Apple play for radio as infotainment keeps failing to include radio and navigation Told by dealer that the infotainment system is not Mounted into the dash and sticks up , so the heat from sun and summer has fried th system. Has been ongoing for over a year just found site to report it . Will not buy another vehicle with infotainment system sticking up out of dashboard

NHTSA ODI 11708847

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.

NHTSA ODI 11707998