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

2018 CX-5 has a cracked or porous (depending who is telling me the issue) cylinder head at 60000 miles. I was told by the Mazda service advisor that the issue is common. I reached out to Mazda for assistance in covering their faulty part and was told they would not cover any of it.

- Rochester, NY, USA

The car would produce white smoke under the engine hood after getting to speed. It would smell like burnt oil. The shop found a crack in the 3rd cylinder. Will need to replace the cylinder head.

- Milwaukee, WI, USA

The engine cylinder head has a crack that has caused the engine oil to leak from the engine. This seems to be a common issue known by Mazda. The oil has saturated the right front brake and portions of the undercarriage, that will also need to be cleaned and or replaced. We had the car looked at a repair shop in Portland OR. they let us know this is a huge problem with this engine and we have not had this repaired as of this note. we will contact or dealer where we purchased the CX-5 and see about getting it replaced. This happened as my Wife was driving from California to our home in Washington. She noticed the oil light was flickering and she found a repair shop in Portland that looked at it and for that the head was cracked. Our car has 89,413 miles on it and has been maintained and does not have any other issues at this time.

- Vaughn, WA, USA

The engine makes a tapping noise during the cold weather that will only go away after the engine has been fully warmed up. This a known issue for with a TSB sent out. However, the issue persist even after repair. The repair is extremely costly and can reach the thousands. This issue also causes worry there is no knowing if the problem will lead to issues further down.

- Carson City, NV, USA

One of the Cylinder heads has a crack in which has cause some oil to leak in the affected area. This is not the 2.5T engine, there is a TSB out for those engines. The affected engine is the 2.5 NA engine.

- Coatesville, PA, USA

Vehicle has a cracked cylinder head at 43,000 miles. It is leaking oil and will lead to further engine damage if not repaired. Dealer inspected and diagnosed the problem. There were no vehicle warnings. It was brought to dealer because it was leaking oil and smelled of burning oil. It appears to be a common problem with Mazda Cx5s.

- Wading River, NY, USA

The contact owns a 2018 Mazda CX-5. The contact stated while driving downhill at an undisclosed speed, the oil warning light intermittently illuminated. The vehicle was taken to the dealer and diagnosed with a cylinder head leak. The dealer replaced the cylinder head and the gasket. The manufacturer was made aware of the failure. The failure mileage was approximately 82,000.

- Northfield, OH, USA

First warning was the oil light came on and I became aware of a leak. When I took it to the mechanic the next day, he described a porous spot on the side of the cylinder head that had opened up and was rapidly losing oil when the engine was running. I understand that this is not a unique problem to my vehicle but is common with this model year. I am concerned that the engine will run out of oil and malfunction causing loss of control at highway speed. The car is currently scheduled for confirmation of the problem with the local Mazda dealer.

- Lake Ariel , PA, USA

Defective sealant used on timing cover, already leaking engine oil at 85000km-?? also confirmed as the same engine prone to cylinder head cracking from poor casting dimensions resulting in engine oil contacting the exhaust manifold and smoking. Possible fire hazard. Engine can seize up from low oil pressure at highway speeds and lock up the wheels causing an accident. Not sure why Mazda hasn-??t issued a recall for this obvious safety concern-?? reminds me of Hyundai/Kia engine problems and now they-??ve been sued and replacing thousands of engines for free.

- Colorado Springs, CO, USA

Engine seems that it cracked. The car has 66K and has good maintenance record. I took my 2018 CX5 to Mazda for a possible oil leak. Mechanic says block has hairline crack, is leaking oil down exhaust manifold and engine needs to be replaced. It seems a known issue with this model & Mazda is aware of the problem. There is no recall or class action lawsuit that either of us found. Mazda has said this car in no longer under warranty. It has 66K and the engine is broken?

- Berkeley, CA, USA