2018 Mazda CX-5 Engine Problems

The contact owns a 2018 Mazda CX-5. The contact stated that while his wife was driving at an undisclosed speed, there was smoke coming from under the hood. No warning light was illuminated. The contact's wife pulled over and discovered that there was oil leaking onto the ground. The vehicle was towed to the dealer, who determined that the #5 and #7 cylinder heads were cracked and needed to be replaced. The vehicle was not repaired. The manufacturer was made aware of the failure. The failure mileage was approximately 100,000.

NHTSA ID

11752421

Incident

Jun 23, 2026

Mileage

100,000 mi

I am writing to formally document a significant engine failure on my 2018 Mazda CX-5 Grand Touring (VIN: [XXX], License: [XXX], Odometer: 78,159 miles). The vehicle began exhibiting visible smoke from under the hood and severe oil leakage — oil was actively pooling beneath the car and leaving a trail. Upon inspection by Cal West Auto Center (San Marcos, CA), the vehicle was diagnosed with a leaking cylinder head gasket requiring full cylinder head removal and replacement. I am aware that Mazda issued Technical Service Bulletin TSB #SA-031-21 specifically addressing a cylinder head casting defect in 2018–2019 CX-5 models equipped with the 2.5L Skyactiv-G engine with cylinder deactivation — the exact configuration of my vehicle. This is a documented manufacturing defect, not normal wear and tear, and the repair estimate I have received is $4,800.84. Given that this failure is tied to a known defect acknowledged by Mazda, I am requesting that Mazda Motor America cover the cost of this repair in full, or provide a clear explanation of what goodwill or warranty coverage is available to me. I am happy to provide the repair estimate, vehicle documentation, and any additional information needed to process this request promptly. Thank you for your attention to this matter. I look forward to your response. [XXX] Cell: [XXX] INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA ID

11752039

Incident

Jul 1, 2025

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 ID

11747961

Incident

Jul 1, 2026

Mileage

83,000 mi

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 ID

11744861

Incident

Jun 12, 2026

The contact owns a 2018 Mazda CX-5. The contact stated that while driving the vehicle he could smell a burning odor, and added that he noticed a puddle of oil on his driveway. The vehicle was taken to an independent mechanic where it was diagnosed to have a cylinder crack causing the cylinder to leak oil all over the engine. The dealer was not notified of the failure. The vehicle was not repaired. The manufacturer was notified of the failure. The failure mileage was 104,000.

NHTSA ID

11742070

Incident

Apr 1, 2026

Mileage

104,000 mi

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 ID

11738764

Incident

Dec 12, 2025

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 ID

11738405

Incident

May 13, 2026

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 ID

11738202

Incident

May 15, 2026

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 ID

11735291

Incident

Apr 27, 2026

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 ID

11734878

Incident

Sep 17, 2025

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 ID

11734839

Incident

Apr 19, 2026

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 ID

11733339

Incident

Apr 22, 2026

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 ID

11731395

Incident

Mar 1, 2026

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 ID

11730869

Incident

Mar 18, 2026

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 ID

11730506

Incident

Mar 3, 2026

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 ID

11730227

Incident

Feb 26, 2026

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 ID

11730122

Incident

Mar 6, 2026

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 ID

11728174

Incident

Mar 17, 2026

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 ID

11727886

Incident

Feb 27, 2026

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 ID

11725144

Incident

Feb 19, 2026

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 ID

11722666

Incident

Mar 7, 2026

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 ID

11722628

Incident

Mar 5, 2026

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 ID

11719213

Incident

Feb 11, 2026

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 ID

11718745

Incident

Jul 15, 2025

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 ID

11716158

Incident

Feb 3, 2026