Cracked cylinder head causing oil to leak
2018 Mazda CX-5
Owner reports · Recalls · Investigations
More warning signs than most CX-5 years
Owner complaints for the 2018 Mazda CX-5 are substantially higher than the model-year median of 133.
About this comparison →How this year compares
Owner complaints by model year
Compare all CX-5 years →Counts vary with age, sales and reporting. They are not failure rates.
What owners reported most
All reported categories
Tap a category to read its complaints. One report may name several components.
When problems were reported
Mileage at the reported incident
Limited mileage data: 83 of 348 reports include usable mileage. There isn’t enough coverage to show a useful chart.
NHTSA’s mileage field refers to the reported incident, not necessarily the filing date. This shows report counts, not the likelihood of a failure.
What to inspect
Issues worth paying extra attention to based on owner reports.
- Engine. Review the 177 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →
- Power Train. Review the 41 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →
- Service Brakes. Review the 32 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →
NHTSA owner reports · September 18, 2026 snapshot.
Engine complaints
177 reportsWhat 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 s…
Read full complaint
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.
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.
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.
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.
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 …
Read full complaint
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.
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,…
Read full complaint
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.
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 i…
Read full complaint
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)
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 PC…
Read full complaint
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.
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 …
Read full complaint
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.
Official recalls
321V875000 · Fuel System, Gasoline:delivery:fuel Pump
Nov 12, 2021
Mazda North American Operations (Mazda) is recalling certain 2018 Mazda3, Mazda6, 2019 CX-3, 2018-2019 MX-5, CX-5, CX-9, and 2019-2020 Mazda2 vehicles. The impeller inside the low-pressure fuel pump may crack and deform, potentially causing the fuel pump to fail.
Consequence & remedy
Consequence: Fuel pump failure may cause an engine stall, increasing the risk of a crash.
Remedy: Dealers will replace the fuel pumps, free of charge. Owner notification letters were mailed July 18, 2022. Owners may contact Mazda customer service at 1-800-222-5500 Option 4. Mazda's number for this recall is 5321K.
19V497000 · Engine; Power Train:automatic Transmission:control Module (tcm/pcm/tecm)
Jun 27, 2019
Mazda North American Operations (Mazda) is recalling certain 2018-2019 CX-5, Mazda6, and 2019 Mazda3 vehicles. A software error in the powertrain control module (PCM) may cause the engine to stall.
Consequence & remedy
Consequence: An unexpected stall increases the risk of a crash.
Remedy: Mazda will notify owners, and dealers will reprogram the PCM software, free of charge. The recall began August 20, 2019. Owners may contact Mazda customer service at 1-800-222-5500, option 4. Mazda's number for this recall is 3719F.
Additional source detail variants (2)
Engine
Mazda North American Operations (Mazda) is recalling certain 2018-2019 CX-5, Mazda6, and 2019 Mazda3 vehicles. A software error in the powertrain control module (PCM) may cause the engine to stall.
Consequence: An unexpected stall increases the risk of a crash.
Remedy: Mazda will notify owners, and dealers will reprogram the PCM software, free of charge. The recall began August 20, 2019. Owners may contact Mazda customer service at 1-800-222-5500, option 4. Mazda's number for this recall is 3719F.
Power Train:automatic Transmission:control Module (tcm/pcm/tecm)
Mazda North American Operations (Mazda) is recalling certain 2018-2019 CX-5, Mazda6, and 2019 Mazda3 vehicles. A software error in the powertrain control module (PCM) may cause the engine to stall.
Consequence: An unexpected stall increases the risk of a crash.
Remedy: Mazda will notify owners, and dealers will reprogram the PCM software, free of charge. The recall began August 20, 2019. Owners may contact Mazda customer service at 1-800-222-5500, option 4. Mazda's number for this recall is 3719F.
18V426000 · Air Bags:side/window
Jun 25, 2018
Mazda North American Operations (Mazda) is recalling certain 2018 Mazda CX-5 vehicles. In the event of a side impact or rollover crash, the side curtain air bags may not properly unfold during deployment. As such, these vehicles fail to comply with the requirements of Federal Motor Vehicle Safety Standard (FMVSS) number 226, "Ejection Mitigation."
Consequence & remedy
Consequence: If the air bags do not deploy properly in a crash, it can increase the risk of injury.
Remedy: Mazda will notify owners, and dealers will replace the curtain air bags, free of charge. The recall began July 31, 2018. Owners may contact Mazda customer service at 1-800-222-5500, Option 4. Mazda's number for this recall is 2718F.
Model-level recall history does not show whether a particular VIN is affected or has received a repair. Check a VIN with NHTSA ↗
NHTSA investigations
0No exact-year investigations in this snapshot.
Illustration