There is a cracked cylinder head cover and the oil leaks from the crack onto the manifold causing smoke and burning smell. I have read several examples on Mazda forums [XXX] ; [XXX] ) of this happening with the Mazda CX-5. A former Mazda mechanic posted he would see a couple vehicles a week at his dealership that experienced this problem. The odor of the burning oil onto the manifold is overpowering when sitting in the car. Some people with the same problem have posted they actually had small fires / burning under the car. In May, 2021, Mazda issued a technical service bulletin TSB # SA-031-21 with a cylinder head redesign for 2018/2019 CX5 models. this is telling of their awareness of the problem. There were no dashboard warnings to indicate the problem - just the burning smell from oil and oil stains in the driveway which caused me to bring the car in. There is substantial evidence that this is a common problem with these model years and it is not related to the mileage of the vehicle - mine has only 37k miles on it. It should be noted that the cylinder head is aluminum and only 2mm thick vs 5-7mm on most vehicles. Mazda should be held accountable and issue a recall and/or extended warranty to address this problem. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

- Buffalo, NY, USA

Car has a ticking sound when in idle mode. My mechanic sent me a few videos to reference and a bulletin from Mazda that attributes the clicking to the Hydraulic Lash Adjuster

- Chicago, IL, USA

Cracked cylinder head at 65,0000 miles

- Vashon, WA, USA

We were driving and noticed some white smoke when we parked, so we took it to a mechanic and he diagnosed: -??Found that only when engine gets up to operating temp that it begins to leak through hairline cracks in cylinder head. Oil leak is severe and recommend not driving and bringing to dealer for possible warranty verification.-?? He told us the issue is specifically on the driver side where there are hairline cracks on the backside, left quarter of the cylinder head.

- Minnetrista, MN, USA

There is a known issue with 2018 Mazda CX 5 related to a cracked cylinder head. I have just under 60,000 miles and I noticed smoke coming from under the hood near the exhaust manifold and a strong odor of burning oil. Dolan Mazda in Reno, NV has confirmed I have a cracked cylinder head and it is the cause of the burning oil. I am concerned that oil leaking from the cracked cylinder head onto the exhaust is a fire hazard. I feel a recall should be issued.

- Reno, NV, USA

We purchased our vehicle from Riley Mazda in September 2018. Shortly after reaching approximately 50,000 miles, we began to notice that the gauges would fluctuate, and there was a slight burning odor in the car cabin. We replaced the air filters for both the engine and cabin, as well as performed an engine oil change. In October, we had a brake flush done when we inquired about the burning smell coming from under the hood. Despite our concerns, the dealership was unable to identify any problems at that time. On a subsequent visit, we paid a diagnostic fee of $220. It was during this visit that the dealership discovered an issue with the engine. The newly identified problems will significantly impair the vehicle's performance and decrease its value. Additionally, we anticipate needing future repairs, which could pose serious safety hazards.

- Norwalk, CT, USA

During cold starts there is a loud ticking sound coming from the top side of the engine. It appears to be one or more HLA.

- Greenville, SC, USA

Cracked cylinder head

- Oklahoma City, OK, USA

Cracked cylinder head causing oil to leak

- Bloomsburg, PA, USA

What component or system failed or malfunctioned, and is it available for inspection upon request" - Engine cylinder head was broken and caused oil leakage How was your safety or the safety of others put at risk? Oil leakage resulted in a smoky smell while driving and could have led to cars on the road or my own car could have skid leading to a fatal accident Has the problem been reproduced or confirmed by a dealer or independent service center? Yes. Has the vehicle or component been inspected by the manufacturer, police, insurance representatives or others" Dealer has inspected. Were there any warning lamps, messages or other symptoms of the problem prior to the failure, and when did they first appear - No warning lamps but there was a smoky smell while driving & visible oil leak under the front hood.

- Duvall, WA, USA

Cylinder head cracked at 46,000 miles causing smoke and oil leakage. This was the root of an almost $6,000 repair, leaving me without a vehicle for 15 days. This issue could also lead to more extensive engine problems in the future.

- Fort Wright, KY, USA

My vehicle has been diagnosed with a cracked cylinder head. The problem began when the vehicle had less than 28,000 miles on it. Mazda is repairing it and has agreed to cover the repair under Mazda Customer Care Assistance.

- Pittsburgh, PA, USA

At approximately 57,000 miles, the cylinder head cracked. It was leaking oil and white smoke was coming out of the engine bay. There were no warning lights. I have since gotten the cylinder head replaced.

- Bonney Lake, WA, USA

At approximately 65,000 miles, a burning oil odor was detected, and we took our vehicle to the nearest Mazda dealership. Techs confirmed a failed master cylinder resulting in a leak, and that this master cylinder failure is common with 2018 CX-5s resulting from porosity in the cast metal wall creating a leak path over time. I was able to retain the failed casting and all parts which were replaced and am saving for records and analysis. Mazda customer service was contacted about the master cylinder casting failure and declined to cover it because the vehicle was beyond warranty period and because the failure was repaired before I was able to establish contact with Mazda customer service. Note that the failure happened in the approach to the holidays, and while efforts were made to establish contact with Mazda service via website chat, e-mail form submission, and phone, they were unsuccessful due to technical issues on the Mazda site and a non-responsive phone line. I can confirm that my local dealership POC provided me with Mazda corporate contact info per my request when the diagnosis was made (e-mail copies available.) The issue was not on my end, as efforts were made again immediately after Christmas, and phone and website chat were immediately successful when attempted. The website chat log indicating their denial and rationale for denial is available. This same vehicle has also had an issue with the front timing cover leaking as several others have noted, and this issue was also acknowledged by local dealership technicians as an endemic issue with this model. The front timing cover issue were identified and repaired within the 60,000-mile warranty. Copies of available correspondence with Mazda, including dealer invoices/receipts, service records for the vehicle (all done at Mazda dealerships) and chat history with Mazda customer service can be provided.

- Appleton, WI, USA

Purchased vehicle from dealership drove 1650 miles, cylinder head began leaking, excessive oil. Took vehicle to repair shop their assessment cracked cylinder head. Warranty expired, dealership refused help in addition to Mazda Corp. unless brought to nearest dealership 140 miles away, with no guarantee. Vehicle is not driveable, I do have photos of the cracks.

- Proctor, MN, USA

The cylinder head on my 2018 Mazda CX-5 developed cracks on the exhaust side, leading to significant oil leakage onto the exhaust manifold. This has caused engine damage and safety concerns. The vehicle is currently at a Mazda dealership, where the issue has been inspected and documented. The component is available for further inspection upon request. The oil leaking onto the exhaust manifold creates a serious fire hazard due to the high heat generated in this area. Additionally, the vehicle experienced burning smells and visible smoke coming through the air vents, which could impair visibility or cause distraction while driving. These conditions place the safety of myself, my passengers, and others on the road at risk. The issue has been confirmed by a Mazda dealership. They provided a video showing oil actively dripping from the cracked cylinder head and stated that the engine requires a full replacement. Mazda dealership video: [XXX] This video contains the engine inspection findings conducted at the dealership during my recent visit. It clearly shows the damage and highlights the issues identified. The vehicle has been inspected by the Mazda dealership service team, who identified the cracks in the cylinder head and documented the oil leakage and related engine damage. There were no warning lamps or messages on the dashboard prior to the failure. The symptoms began with a noticeable burning smell inside the cabin, followed by a slight mist coming out of the air vents and smoke from under the hood. Oil leakage was later observed on the ground, and the coolant level appeared empty. I-??ve received a video inspection of my vehicle from the service center on March 7, 2024 with no concerns at that time, which you can view here: [XXX]. This link leads to TruVideo, a platform that many dealerships use to share service videos with customers. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

- Williamstown, NJ, USA

Excessive intermittent Engine vibration at 10 mph to 40 mph at very light load, very light throttle. If a very light throttle Is applied or removed the vibration seems to go away. In light traffic at low speed the vibration is of concern as to the damages it may further cause. On 11/19/2024 Boucher Mazda charged me to perform PCM and TCM updates which did not correct the problem. On 12/11/2024 Russ Darrow Mazda of Greenfield Wi, thought a motor mount KN-39-040 should be replaced. $540.28 later, the problem is worse. I believe the problem is caused by the CYLINDER DEACTIVATION issue Identified by Recall 3719F which I was never notified. This is a safety issue, because I don-??t know when the engine is to fail or stall or what the damages will be. I pay a large fee for Diagnosing only to get -??LIP-?? Service.

- Lake Geneva, WI, USA

There was a burnt rubber smell coming off the vents, took to dealership and they confirmed there was an issue with the front timing cover and was replaced. Less that a week later, there was smoke coming from the hood of the car. Took back to dealership unaware if it was recurring issue but it was determined there was a NEW oil leak due to faulty cylinder head needing replacement on my car which has less than 50,000 miles. While there was no warning lights, the car was unsafe to drive in that condition.

- Los Angeles, CA, USA

The cylinder head cracked while waiting for a light to change at a busy intersection, causing heavy smoke to enter the vehicle through the air vents with the heater on. The smoke filled the car quickly, causing my wife and me to exit the vehicle at the very busy intersection. A local independent service center diagnosed the problem. I was unable to drive the vehicle to the manufacturer for safety reasons and smoke filling the cabin. No warning lights were displayed. This vehicle was maintained following the manufacturer's recommendations throughout its 77,000 mile life.

- New Windsor , NY, USA

We are a senior citizen couple driving this 2018 Mazda. Went out to garage to find a significant size area of oil spillage on the floor. The car has just over 25,000 as we are low mileage drivers. Took to a mechanic to find out it is a cracked head and oil is steaming out of the crack.i have since learned that Mazda is well aware of the weakness in this model and has chosen not to do anything about it. Our car is out of warranty. It would be a hardship for us to repair. And if repaired, would it happen again" This has recall written all over it, as well as a class action suit. I would like our vehicle repaired at no cost to us. How long were they aware of this issue" I have found hundreds of complaints. I prefer not to pursue this legally but this is unacceptable by Mazda. This was my second Mazda purchase but will be my last if they cannot stand behind their products.

- Indianapolis, IN, USA