The head on the 2.4L engine of the 2019 Mazda CX5 has shown a manufacturing defect that Mazda has addressed in certain models, but not all of the models with this engine. This leaves a large amount of vehicle owners with the financial liability to pay out of pocket for Mazda's engineering and manufacturing defect that they know about. The oil leaks onto the exhaust manifold creating a fire hazard. When driving our car, we cannot use outside air on the vents, A/C because the intake pulls in smoke coming from the engine compartment. I brought the car in today to Mazda and was denied any help in the repair, I am continuing with Mazda corporate to try and reach a resolution. Currently this will be roughly a $7000 repair. I do not have an estimate yet from the dealership.

- La Mesa, CA, USA

The engine cylinder head cracked and is leaking engine oil. This component is available for inspection at Liberty Mazda or by an independent certified mechanic upon request. The cracked cylinder head caused significant engine oil leakage, which created the following safety risks: Sudden loss of engine power or stalling while driving Smoke emission from the engine bay Potential fire hazard if leaking oil contacted hot engine components These conditions placed both the driver, passengers, and others on the road at risk. The cracked cylinder head and associated oil leak were diagnosed and confirmed by Liberty Mazda, the authorized dealership that performed prior repairs on this vehicle. The dealership documented the issue and provided a repair estimate of approximately $5,400. No independent service center has inspected the vehicle at this time. The vehicle and cylinder head have only been inspected by Liberty Mazda. Mazda Corporate has not physically inspected the vehicle, but all service records and documentation of prior repairs have been submitted to them during the warranty dispute process. There has been no inspection by police, insurance representatives, or other third parties May 2025: The vehicle intermittently struggled to accelerate. At that time, no dashboard warning lamps illuminated, and the dealership initially reported no issues. June 2025: Following the timing cover repair, the vehicle experienced engine oil leakage due to incorrect sealant installation, which was documented. February 10, 2026: The dealership repaired the oil pan seal and replaced the sealant, refilling engine oil. February 14-?"15, 2026: Approximately four to five days after the February 10 service, the cylinder head cracked, causing a significant oil leak. All symptoms and related service events are documented in Liberty Mazda-??s service records.

- Rapid City, SD, USA

The vehicle's cylinder head has developed a structural crack at on the casting, a known manufacturing defect identified by the manufacturer in Service Advisory SA-037/23. This failure is causing pressurized engine oil to leak directly onto the hot exhaust manifold while the vehicle is in operation. The leaking oil is pooling on high-temperature exhaust components, creating a significant risk of fire while driving. The leak generates heavy smoke and noxious burning oil fumes that are entering the passenger cabin through the HVAC system, causing respiratory issues

- Buffalo, NY, USA

The vehicle has suffered a crack of the Cylinder Head Assembly which leads to engine oil leaking onto hot exhaust and fire hazard. This defect is officially documented by the manufacturer in Service Alert SA-031/21, which identifies a trend of aluminum heads cracking and leaking pressurized oil directly onto the hot exhaust manifold. Although Mazda has issued a 10-year/120,000-mile warranty extension (Program CSP11) for the exact same casting failure in its Turbo-equipped models, it has refused to provide similar "Goodwill" relief for my vehicle, despite it suffering from the identical engineering flaw. Mazda-??s refusal to cover a verified latent manufacturing defect that poses a significant fire hazard is arbitrary and unfair. I am requesting that Mazda North American Operations provide full reimbursement for the $6,788.51 repair

- Sierra Madre, CA, USA

I am being told there is a crack in the cylinder head that is a known issue for these vehicles. I have done some research online and it says that they installed defective cylinders in vehicles that were made between the years 2018-2020 leaving vehicle owners to pay thousands of dollars out of pocket due to a manufacturing defect. My car was smoking and smelling like something burnt even inside the car causing the driver to inhale those fumes, I took it to the shop and it turns out that the cylinder head is cracked and leaking the oil.

- Livingston, TX, USA

Drove 39 miles, around ~55 minutes. Parked the car, realized that I parked a little too far from the spot, car just stalled while rolling. Pressed accelerator, nothing. Turned off the car, tried to start again, it cranked but didn't start. Had to tow it to the nearest mechanic (total of ~2 hrs until my car got picked up and dropped off), mechanic calls me and tells me my car started fine. I'm thinking it could be 5321K recall but not sure as my VIN is not in the recall nor did I get any recall notice. What component or system failed or malfunctioned, and is it available for inspection upon request" - No idea. How was your safety or the safety of others put at risk? - Got stranded for hours in the parking lot. Has the problem been reproduced or confirmed by a dealer or independent service center? - No Has the vehicle or component been inspected by the manufacturer, police, insurance representatives or others? - No Were there any warning lamps, messages or other symptoms of the problem prior to the failure, and when did they first appear" - Yes, fuel cap like icon and check engine light were on when trying to start the car after it stalled. The car would crank but not start.

- Manassas, VA, USA

1. What component failed, and is it available for inspection? Component: The Engine Cylinder Head. The Failure: The cylinder head failed due to a structural crack caused by overtightened bolts (manufacturing defect), resulting in an engine oil leak. Confirmation: The defect is confirmed and resolved. Wayne Mazda (NJ) acknowledged the failure and replaced the cylinder head under the CPO Warranty last month. The issue has not returned since the replacement, proving this was indeed a hardware defect. 2. How was your safety put at risk" Fire Hazard: Before the repair, for a duration of one year, the vehicle leaked engine oil onto the hot exhaust manifold, creating a persistent fire risk. Toxic Exposure: My family and I were forced to inhale burning oil fumes inside the cabin for months due to the dealer's delayed diagnosis. This posed a significant health hazard. 3. Has the problem been reproduced or confirmed" Yes. The defect was initially identified by independent service centers (when the dealer failed to find it) and was ultimately verified and repaired by Wayne Mazda. The fact that the dealer performed the repair under warranty is an admission of the manufacturing defect. 4. Financial Damages & Request for Reimbursement: Since Mazda has admitted liability by fixing the vehicle, I request reimbursement for the losses incurred due to the delay in diagnosis: $2,000+ in Independent Repairs: Because Wayne Mazda initially failed to diagnose this warrantable defect, I was forced to pay independent shops to diagnose and attempt to fix the oil leak to keep the vehicle safe. These costs were a direct result of the dealer's inability to identify the manufacturing defect. $159.29 in Uber Fees: Mazda failed to provide a loaner vehicle during the major powertrain repair, forcing me to pay for my own transportation. Conclusion: I am filing this report to: Document this safety defect (Overtightened Cylinder Head Bolt / Oil Leak) for NHTSA records, as it poses a fire

- Edison, NJ, USA

On 12/10/25, my 2019 CX5 NA had major oil leak after smelling a burning smell for a few days. Took it into local mechanic and he couldn-??t find the leak, did an engine wash and additional testing before identifying a crack in the cylinder head; the leak was coming from the exhaust manifold. There was oil all over the engine and the underbelly of the vehicle; according to the mechanic, I was lucky the car didn-??t start on fire with the amount of oil. I was informed that this is a common problem with the turbos and the NAs but the extended warranty only included the turbo engines. Contacted Mazda customer experience and set up an appointment. Vehicle went to the Mazda dealership on 12/15 and it was confirmed that there was a crack in the cylinder head and received an estimate of $11,000 needed for repairs. $7000 of that was for a new cylinder head. This was after an independent mechanic inspected my vehicle and stated everything looked good besides the main issue and needing new rear breaks in the next few months. 12/15-contacted Mazda customer experience and and case file was opened. 12/16-contacted customer experience back due to not receiving a call and received the name and extension of the assigned case manager. 12/17- still had not received a call back and left voicemail for case manager. Requested a call back to myself and the dealership; received a call back a few hours later and I was never asked what happened but was informed that Mazda corporate could not help me due to the warranty being expired. I am now required to pay over $250 to the dealership for an inspection of the vehicle I never requested. There were initially no warning signs but then the low oil light came on after 3 days of smelling something burning.

- Palatine, IL, USA

The 2019 CX-5 AWD with the 2.5L NA engine (with Cylinder Deactivation) has an engine oil leak coming from the cylinder head area. The Mazda dealer confirmed the leak source and found burnt oil on the exhaust. The component is available for inspection. The leak location and symptoms are consistent with the known porous/cracked cylinder-head defect documented in this engine family. Full confirmation requires teardown. In early Dec 2025, a burning oil smell began, then thick white smoke came from under the hood while driving and after stopping. This created an immediate fire risk, and rapid oil loss could cause sudden engine failure or stall in traffic. The issue was inspected and confirmed by an independent mechanic, who noted the leak could only be traced after removing the exhaust manifold. The Mazda dealership then inspected it and confirmed the leak source at the cylinder-head area and the burnt oil residue. The problem has been reproduced and confirmed by both the independent mechanic and the Mazda dealer. No warning lights or messages appeared prior to the smoke. Mazda has an extended warranty program for the same cylinder-head defect on the Turbo engine, but no equivalent coverage exists for the NA engine, despite the identical safety risks.

- San Marcos, CA, USA

While driving a short distance, my engine overheated and there was a strong burning smell. The cylinder head was cracked, causing a significant oil leak. The car is currently at the dealership but is available for inspection upon request. The defective cylinder head is leaking engine oil directly onto hot exhaust components. This creates an immediate risk of engine fire and causes smoke to enter the vehicle cabin, impairing visibility and driver health. The vehicle was diagnosed by an authorized Mazda dealership. They confirmed the cylinder head is cracked and requires replacement. My mechanic advised this type of leak could lead to engine overheating, sudden power loss, or potential fire risk and should not be driven. Mazda has issued prior Technical Service Bulletins and warranty extensions for similar cylinder head/manifold cracking issues on the 2.5L turbo engine, but no program exists for the non-turbo engine, despite identical problems. Mazda should be held responsible for this safety issue. Mazda is aware of this manufacturing defect but has not recalled these engines to be repaired or replaced if they are outside of their warranty period, placing costly repairs and potentially life-threatening situations on their customers. The repair is replacement of the cylinder head/sleeve or replacement of the engine block, which has since been modified by Mazda to resolve this issue. Mazda-??s refusal to extend reimbursement to non-turbo owners is unfair and leaves affected customers with no support for a known manufacturing flaw. I urge NHTSA to investigate this recurring engine defect in non-turbo 2019-?"2020 Mazda CX-5 models and encourage Mazda to offer equal reimbursement.

- Jacksonville, FL, USA

Question 1 - What component or system failed or malfunctioned, and is it available for inspection upon request" Answer 1 - The Engine Cylinder Head. The cylinder head developed a crack, causing a significant oil leak. The car is currently at the dealership but is available for inspection upon request. Question 2 - How was your safety or the safety of others put at risk? Answer 2 - The defective cylinder head is leaking engine oil directly onto hot exhaust components. This creates an immediate risk of engine fire and causes smoke to enter the vehicle cabin, impairing visibility and driver health. Additionally, the loss of engine fluids creates a risk of sudden engine failure or stalling at highway speeds. Question 3 - Has the problem been reproduced or confirmed by a dealer or independent service center Answer 3 - Yes. The vehicle was diagnosed by an authorized Mazda dealership. They confirmed the cylinder head is cracked and requires replacement. The dealership acknowledged the failure and offered a partial repair discount, confirming their diagnosis of the defect. Question 4 - Has the vehicle or component been inspected by the manufacturer, police, insurance representatives or others" Answer 4 - Yes. The vehicle has been inspected by an authorized Mazda dealership technician acting as a representative for the manufacturer. I have also escalated the issue to Mazda Corporate (case number can be provided upon request), who reviewed the dealership's findings but refused to cover the full repair cost. Question 5 - Were there any warning lamps, messages or other symptoms of the problem prior to the failure, and when did they first appear? Answer 5 - I noticed an oil leak on my driveway. I noticed it and brought it in to be looked at the first week of November 2025.

- Hamburg, NY, USA

What component or system failed: The cylinder head failed due to cracking around the exhaust manifold, resulting in exhaust and coolant leakage. My independent mechanic and the Mazda dealer both confirmed this was the source of the burning smell and engine risk. The failed parts are currently in the possession of the Mazda dealership and available for inspection upon request. Safety risk: The failure created a strong burning rubber smell inside and outside the vehicle while driving. My mechanic advised this type of leak could lead to engine overheating, sudden power loss, or potential fire risk if not caught early. I frequently transport children in the vehicle, and the unexpected engine damage posed a significant safety concern. Has the problem been reproduced or confirmed: Yes. The issue was first diagnosed by an independent, certified mechanic and then confirmed by the Mazda dealership, who determined the cylinder head had to be replaced due to premature cracking and leakage. Has the vehicle/component been inspected: Yes. The vehicle has been fully inspected by an independent mechanic and the Mazda dealership service department. The dealership stated the failed cylinder head will be sent to Mazda for engineering review. Were there any warning lamps or symptoms before failure: There were no warning lights or error messages prior to the failure - which is alarming. The only initial symptom was a strong burning rubber smell that began shortly before the diagnosis. No overheating warnings appeared on the dash before the problem was confirmed. Additional context: The vehicle has 40,000 miles, has been fully maintained according to schedule, and is garage-kept. The Mazda service department acknowledged this failure is unusual and premature. Mazda has issued prior Technical Service Bulletins and warranty extensions for similar cylinder head/manifold cracking issues on the 2.5L turbo engine, but no program exists for the non-turbo engine, despite identical symptoms.

- Sewickley, PA, USA

The Cyclinder Head cracked. This could cause the engine to fail, and leaving the driver on the highway or other unsafe locations of travel. The certified repair shop along with the insurance adjuster advised it was a manufacturing defect. The warning sign was an oil burning smell inside the vehicle while stationary and inside the garage.

- Sykesville, Md, MD, USA

Confirmed cracked cylinder by dealership, led to dumping of oil while vehicle was in motion on the highway. Vehicle/engine could have caught fire at any moment. There were no engine warnings that appeared on the dash. This is consistent with other CX-5 complaints on NHTSA. Vehicle had 55,000 miles on it at time of incident, and needed $8,000 worth of repair. Please recall!!

- Kansas City, MO, USA

In August 2025, we brought our Mazda CX-5 (non-turbo engine) to a Mazda service center and paid nearly $3,000 for repairs, including replacement of belts and other related service. Despite this, we continued to experience a burning smell from the vehicle. Shortly thereafter, the problem escalated -?" the burning smell persisted and smoke began to appear. Mazda is now demanding an additional $4,500 to replace a cracked cylinder head. This defect must have been present when the car was serviced in August, and the initial repairs failed to identify or correct it. While there is an NHTSA Technical Service Bulletin for the turbo version of this engine, there are numerous complaints online about the same defect in the non-turbo model, which is what we own. This indicates that the problem is not isolated. Mazda should be held responsible for this safety issue. A cracked cylinder head that leads to burning smells and smoke is a serious hazard that could cause engine failure or even fire. Consumers should not be forced to spend thousands of dollars on repairs for what appears to be a widespread defect and when our vehicle has only $50k miles and it should last for the life of the vehicle.

- Old Bethpage, NY, USA

Cracked/Leaking Cylinder Head on my 2019 Mazda CX5. It is understood that Mazda has extended warranty for the Turbo Model (CSP11) of this car, but not the standard engine, even though they both are displaying the same issue in many 2019 CX5s. Quoted at $6000 for a vehicle under 90K Miles. Issue needs to be escalated.

- Arlington, MA, USA

Dealership service department found a cracked cylinder head. This issue has been reported to NHTSA by Mazda. The car is being serviced and this issue was found. I-??m attaching photos and also report from dealership l.

- Richmond, CA, USA

Cracked Cylinder Head.

- Rosemount, MN, USA

Timing cover oil leak. This is the same issue reported in technical bulletin #01-006/23 issued on 04/26/2023. There is oil leaking and the engine is smoking. No engine warning lights or other messages appeared. My car is a 2019 mazda CX-5 and has 31,954 miles. This problem has been confirmed by both an independent mechanic and the dealer service center. On 08/22/2025, I took my vehicle to dealer service for the repair. I also submitted a ticket to Mazda care for review of the case.

- Richmond, CA, USA

For the 3rd or 4th time since I have own this car I experienced a loss of acceleration when attempting to make quick acceleration while attempting to merge with traffic. Acceleration is fine around town where quick acceleration is not appropriate. But the first attempt to merge with flowing traffic the car will slowly accelerates to about 30 mph and no more regardless as to position of accelerator pedal. On all occasion this bad behavior has this first drive of the day - going to work in the a.m. There is often a warning message indicating the safety radar is not working due to limited visibility which is a very common warning in the a.m.

- Batavia, IL, USA