Cracked cylinder head. Major oil leak. Oil light came on but then turned off. No other warning light. No engine light came on. The vehicle was taken to the dealer for diagnosis.

- Marysville, OH, USA

The cylinder head in the engine cracked while I was driving. The vehicle was leaking oil profusely and was down a quart after the oil had been changed the week prior. There were no warning lights or indication and I had just had the vehicle in the dealership the week before. I'm a disabled driver that requires hand controls so if I needed to exit the vehicle and move away from it it would not be possible. It's been at the dealership since 2/24/25. I have found numerous other people that have experienced the same issue online.

- New Lenox, IL, USA

The cylinder head on my 2019 Mazda CX-5 failed prematurely due to a known defect. The vehicle is currently at Fred Beans Mazda in Mechanicsburg, PA, where the issue has been diagnosed and confirmed. The defective component is available for inspection upon request. This failure created a serious safety risk due to an oil leak, which led to smoking from the engine bay and a potential fire hazard. If the oil had ignited, this could have caused severe vehicle damage or injury. Additionally, the failure could lead to a sudden loss of power while driving, increasing the risk of an accident. The problem has been reproduced and confirmed by the dealership, and Mazda has been contacted regarding assistance. They have acknowledged the issue but have not provided full coverage for the repair. Prior to the failure, there were no warning lights or messages. The only symptom was an oil leak, which led to smoke coming from the engine. This issue appears to be a common problem with this model, and Mazda should take responsibility for addressing it properly before it causes serious harm.

- Mechanicsburg, PA, USA

This concerns a 2019 Mazda CX5 with approximately 52,000 miles - the engine of this vehicle is the 2.5L naturally aspirated version. Driving the vehicle with the HVAC system on resulted in a burning oil smell coming through to the cabin. Upon owner inspection, engine oil was seen as coating the underside of the vehicle in various areas. The oil pan drain plug and oil filter were both found to be tight and not leaking oil. The vehicle was taken to a nearby Mazda dealership for inspection on 2/26/2025. On 2/27/2025, Mazda technicians state that the cylinder head on the vehicle engine requires replacement. Replacement is quoted to be in excess of $5000. Reviewing the issue online shows numerous similar cases of engine cylinder head failure. This vehicle comes equipped with cylinder deactivation which seems to have a higher rate of failure regarding cylinder heads and a potential design flaw with cylinder heads manufactured in a time frame of 2018-2020. Leaking oil could potentially start a fire as the oil drips onto the exhaust manifold when the car is at operating temperature.

- Cincinnati, OH, USA

While driving the vehicle, I started smelling a burning smell about 10 days ago (2/17). I also felt a slightly reduced engine performance and could see the car emitting smoke from the engine bay. I had no warning lights on my dash. For all I know, the engine could've blown while I was driving on the road. Upon taking the vehicle to the dealership 2 days ago (2/25), they informed that my car has a cracked cylinder head, and there was no apparent reason why this would happen. The vehicle has only been inspected by the dealership thus far and I was quoted $5,700 to fix the issue. Upon looking up the problem, I see this is a common issue, with many having experienced it before, but no TSBs issued for this. There is a CSP issued for vehicles of the same year, but limited to the Turbo version on the engine. Unfortunately, I do not have any warranty on the car currently.

- Bloomfiled Hills, MI, USA

I hope this message finds you well. My name is [XXX], and I am the owner of a 2019 Mazda CX-5 purchased as part of the Certified Pre-Owned (CPO) program. I am writing to formally address two concerning issues related to my vehicle-??s warranty coverage and its safety. 1. Warranty Coverage for Drive Belt Tensioner: During a recent visit to your dealership, I was informed that the drive belt tensioner on my vehicle is not covered under the warranty. This contradicts the coverage listed on your official Mazda CPO Warranty, which specifies that the Limited Powertrain Warranty includes the engine, timing chain, tensioner, and associated components. The drive belt tensioner is clearly referenced in this section, yet I was told it falls under wear and tear and is not covered. I kindly request a detailed explanation regarding this discrepancy. I believe the information I was given does not align with the warranty-??s stated coverage, and I am concerned that the dealership is not honoring the terms of the warranty as outlined on your website. 2. Ongoing Noise Issue: Additionally, my vehicle has been making an unusual noise, which I reported during my visits to two separate Mazda dealerships. Unfortunately, despite multiple attempts to diagnose the issue, neither dealership has been able to identify the source of the noise. This situation has left me feeling unsafe while operating the vehicle, as I am unsure of its origin or potential impact on my vehicle-??s performance or safety. I would appreciate it if you could escalate this matter and offer assistance in determining the cause of the noise, as well as ensure that all components of the vehicle are functioning properly. The lack of resolution is not only inconvenient but also concerning from a safety perspective. Request for Resolution: I trust that Mazda values its customers and will make every effort to resolve these issues in a timely manner. I respectfully request that the drive belt tensioner be covered und INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMA

- Apple Valley, CA, USA

Oil started leaking while car was idling causing smoke to enter the cabin as well as all under the hood. Car was undriveable at this point. She was lucky there was no traffic. Car had to be towed and cylinder head was cracked. Mazda has a known faulty cylinder head problem they have refused to fix and this caused a safety issue. Vehicle will not be able to be inspected as we had it towed to get fixed immediately. The service center did confirm this is the issue and there were no prior issues before this.

- Aurora, CO, USA

As I was driving, a burning smell emanated from the car. There were no check engine lights on. When I pulled over, I saw a lot of smoke coming from the engine. I checked the oil level and it was above the minimum line bit just barely, even though my husband had just done an oil change on it. I refilled the oil and continued on my trip. The problem repeated for several dqays until I got home and took it to the Mazda dealership. They reported the following: "Cylinder Head Assembly: oil leaking out of back of head, recommend replacing cylinder head and related gaskets. The cylinder head sits above the cylinders on top of the cylinder block. It closes in the top of the cylinder, forming the combustion chamber. This joint is sealed by a head gasket. In most engines, the head also provides space for the passages that feed air and fuel to the cylinder, and that allow the exhaust to escape." This service is $5600! My car only has 80K miles on it. This is a safety issue because there was no warning. No check engine light appeared and there was no warning.

- Grand Rapids, MI, USA

I own a 2019 Mazda cx 5 and it has 78,000 miles. I noticed smoke coming from the engine and a lot of oil leaking on the ground. I brought the car into my independent service center and they confirmed that there was a crack in the engine cylinder head. There is a TSA # SA-031-21 on this problem. I feel that my safety was at risk, since the engine could have seized while driving. This vehicle is available for inspection upon request. No warning lamps or messages were displayed, however there was a strong odor of burning oil. This problem occurred on 1/9/25 and it has been in the service center since.

- Dedham, MA, USA

Car was purchased in June 2019. Car started smelling like burning oil and started finding oil pooling under the car around November 2024. At time the incident was discovered, car only had 38k miles. There was no warning lights or indication there was an issue other than the smell and small pool of oil under car. The Mazda service manager immediately knew what the issue was and told me they were going to confirm with a full inspection and diagnosis. I was told that I have a cracked cylinder head and I will need to have it replaced. Warranty ended few months prior so they will not cover. I was told it would cost $4589.76. The Mazda service department told me that this is a common issue and to hold off on repair and contact Mazda corporate since warranty just ended. They topped off my oil and told me to keep an eye on the oil level and to wait to hear back from Mazda corporate.I submitted a case with Mazda and the customer care specialist told me that they cannot guarantee they will cover this. Within a week, the temperatures got colder and issue got worse. Low oil light came on, topped off with oil. Lost 4 quarts in one day. Called Mazda service and they told me to top off oil and come drop car off immediately. Upon researching this issue, the cracking of cylinder heads in Mazda CX-5 vehicles, particularly those with the 2.5-liter (NA) engine were widespread and discussed in online forum. The contributing factors of the issue point to a design flaw of the cylinder head due to the cylinder deactivation technology and a manufacturing defect due to the cylinder head casting process based on reports and discussions within the automotive community. A TSB (SA-013/22) has been released for the affected cylinder head with a modified replacement. This seems to be a significant and widespread issue that can cause entire engine to fail and require full replacement. Oil leaking on to the hot exhaust near other engine parts could ignite and put myself or others at risk.

- Oklahoma City, OK, USA

Engine block cracked, passenger cabin filled with noxious odder. Vehicle was suddenly leaking oil at high rate.

- Chanhassen, MN, USA

My 2019 Mazda CX-5 suddenly developed a major oil leak within the last 7 days. My car has only 44,350 miles and I have had all scheduled and required maintenance completed timely, including oil/filter changes, coolant level checking and maintenance, etc. I took the car to an independent mechanic who diagnosed the problem as a cracked cylinder head. I then took the car to a local Mazda dealer who confirmed the diagnosis and informed me that there would be no warranty coverage as my 60,000 mile/60 month powertrain warranty had expired 60 days earlier. Some two years earlier my car's check engine light came on and overheated. I took it to the same local dealer, who replaced the coolant control valve & related components. In November 2024 I received a "Warranty Extension Program" letter from Mazda about the same fail-safe thermostat problem. I believe this is relevant and related to the cracked cylinder head since almost all instances of a cracked cylinder head are due to engine overheating. This issue put me at risk as I was close to driving the car with no oil and oil leaking heavily onto very hot engine components that could have resulted in a fire. I am now facing repairs to this car between $4,800 and $6,000 and given the faulty/defective cylinder head from Mazda, I could face this safety issue again, as it will be replaced with a similar cylinder head from Mazda!

- Sheffield Lake, OH, USA

I started to smell a burning smell while I was driving and noticed smoke coming from under the hood along with the burning smell. When I parked the car I noticed a bunch of oil leaking from under the car. I took the car to get checked out and there was oil all under the bottom of the car and it was confirmed that there was a very bad oil leak which occurred due to a crack in the cylinder head. No check engine lights or any indication of this issue aside from discovering the burning smell, smoke from under the hood, and a significant amount of oil underneath the car. The car hasn-??t been driven in a month because of this issue. When you turn the car on you can hear a ticking sound coming from under the hood. The bad part is there was no indication. A 2019 with 50,000 ish miles shouldn-??t have this problem and I confirmed that with mechanics and Mazda. This is a safety risk as you can-??t safely drive the car without being concerned about the lack of oil in the car due to the leak as well as the smoke coming from under the hood, not being able to drive the car thus resulting in needing the car towed in order for the car to be serviced for this problem. I was told that if the oil continues to leak and if I was to drive it the engine could start to have issues and possibly turn off due to the leakage. This leak had oil all over the exhaust system as well.

- Mechanicsville, VA, USA

This car has less than 37,000 miles on it it has significant oil leaks from the valve cover gasket, it-??s timing cover gasket and now it had been determined it has a cracked cylinder head. This was covered by 3 Service alerts with the cracked cylinder head being SA-031/21. None of the dealers notified us of the issue when serviced Galpin Mazda and New Century Mazda. But Big O Tires did. The two oil leak gasket repairs cost over $1600. The car is 8 months past warranty. The car is burning oil when driven. Due to the leak and the smoke particles and smell enter the cabin. The engine smokes when shut down instill it cold down. The smoke particles in the cabin are dangerous. The engine oil light appeared in late November (my daughter-??s car, she is away at college). We found out the depth of the oil leak issues the second and fourth week of December. The fact that the dealers did not notice us or do preemptive repairs is a major failure by the Mazda organization.

- Pasadena, CA, USA

Brought 2019 Cx-5 to local dealer with complaint of strong smell and smoke coming from hood. Cracked cylinder head at only 21k miles. Known flaw for this particular make and model. Only 6 months out of warranty. Mazda refuses to make it right and only extended warranty for turbo engines. Mazda needs to make this right for ALL engines with this issue.

- Aston, PA, USA

The 2019 has a creaked cylinder with 40000 miles on it. This is a problem with that has been happening. We are 4 months out of the warranty with May 2024.

- Lincoln, NE, USA

My Mazda CX-5 was found to have a cracked cylinder in the engine and was profusely leaking oil. When I spoke to the dealership they denied seeing this regularly, however, upon doing research on reddit, it is found to be more pronounced than indicated. There was no known cause indicated, however, on reddit it appears that the original casting done in Mexico maybe the culprit because it is so thin and causes it to crack between 40-50k miles. There is no other sign or warnings, besides an obscene amount of oil leaking. The failure of this could cause the engine to fail while driving. This is a significant risk.

- Glen Allen, VA, USA

Vehicle has 40k after a oil change noticed oil spots on pavement took it back to the garage that did the task, was told that the leak was near cylinder #2. Called Mazda customer service and was informed that my warranty expired in May of 2024. my mechanic called Mazda parts to get the price of cylinder head and was told that they had a run on cylinder heads due to defective heads coming from the Factory, SHOULD BE A RECALL ON THE MAZDA.

- Clearwater, FL, USA

The head gasket cover is leaking leading to a great deal of smoke. The car should not be driven per my mechanic due to risk of fire

- Seymour, CT, USA

I have 115k miles on my 2019 CX5. Never has any issues. Now all of a sudden I have a cracked cylinder head leaking oil. I was smelling smoke but mot seeing it. I took into dealership they noticed oil dripping thus why smell. Its a $4500-5000 job. I cannot afford this. This should not happen at this kind of mileage. My warranty just expired too. Mazda needs to cover these type of repairs

- York, PA, USA