2018 Mazda CX-5, 2.5L Naturally Aspirated Engine The vehicle has been diagnosed with a leak from the cylinder head cover, resulting in engine oil dripping directly onto the exhaust manifold. This issue causes noticeable smoke and a strong burning oil odor inside the cabin while the engine is running. This defect presents multiple serious safety concerns: 1) Health hazard due to prolonged exposure to burning oil fumes inside the vehicle. 2) Fire risk from oil contacting hot engine components. 3) Potential engine failure, which could lead to vehicle stalling or loss of control, increasing the risk of a crash and possible loss of life. Mazda issued Technical Service Bulletin TSB #SA-031-21, which introduced a redesigned cylinder head for 2018–2019 CX-5 models. The release of this TSB indicates Mazda’s awareness of the underlying design flaw. There is substantial evidence, including numerous owner reports, that this is a widespread issue affecting these model years. The defect is not related to vehicle mileage or user negligence. Mazda should be held fully accountable and take corrective action by issuing a formal safety recall or offering an extended warranty to affected owners. Immediate attention to this matter is necessary to protect consumer safety and prevent future incidents.
2018 Mazda CX-5 engine complaints
Page 3 of 7: complaints 41 to 70 of 186, newest first, as owners wrote them.
Cracked cylinder head leaks oil directly onto hot exhaust, causing smoke, fumes in cabin and a fire risk.
the cylinder head has a crack in it witch sprays oil all over the engine.it also sprays oil on to the very catalitic converter that's very hot .smoke is everywhere and iam afraid it will cause a fire
I own a 2018 Mazda CX-5. I currently have 64,770 miles on the car. I have had a burning smell and smoke coming from the engine. The car was taken to the dealer (John Kennedy Mazda Conshohocken) and I was told it was fixed by replacing a gasket. The smell and smoke persisted. I took it back to the dealer and now I am told there is a leaking cylinder head. I do not feel safe driving this car especially with my kids in the car while the engine is smoking. I have had to pull over on the highway due to this. No warning lights were on until a week prior to taking it back a second time when my oil light finally came on.
Engine Cylinder heads started to leak at 75k miles causing oil and coolant to leak and puddle. This was after a fuel pump recall.
The radio changes stations by itself, speakers/music goes in and out. The screen freezes and cannot change stations. And also the car lags on taking off sometimes. Often smells like fuel when you turn on the car, Assuming a fuel pump issue, not sure. I spoke to the salesman who sold me the car (adam) within less than 30 days of having the vehicle and told me the electrical issue with radio would be covered. Then when I called to have the issue fixed I was told it wasnt going to fixed on their behalf. This car was sold to me with a few issue that I was not aware at the time of purchase.
While waiting at a stop light the engine will turn off. This has happened three times since I’ve owned the car 2/16/2025.
Issue with the engine cylinder head leaking engine oil from the side of the cylinder head, where the casting has a defect. Leaks engine oil onto the flashing for the exhaust and exhaust manifold, where it could catch fire. The problem has been confirmed and diagnosed by a licensed mechanic. However, the dealer would not take responsibility for repair or assistance in repair. There are no warnings, while driving and after stopping, the smell of burning oil comes into the car and also smoke from the engine compartment.
Sometimes, the breaks will not go all the way down to the floor and act like theyre not working. it's very odd and only does it once in a while. i have constant issues with the technology in the car. it changes my music, the buttons get stuck and my it acts up. my aunt has the same model and is running into the same issues. i never received a letter in the mail about the last recall and have had issues where it doesnt seem like my engine is getting the power it once did. this was early on after i got the car. my gas mileage has significally decreased even after oil changes.
The contact owned a 2018 Mazda CX-5. The contact stated that while her daughter was driving at 35-45 MPH, the vehicle was shaking and rattling. There were no warning lights illuminated. The vehicle was taken to the local dealer where it was diagnosed that the wheel bearings were faulty. The vehicle was repaired but the failure recurred. The vehicle was taken to the local dealer again where it was diagnosed that there were loose parts in the engine. The vehicle was repaired but the failure recurred. Additionally, the brake light was illuminated. The vehicle was taken to the dealer where it was diagnosed that the switch and mat were causing the failure. The vehicle was repaired and returned to the dealer. The manufacturer was contacted. The failure mileage was approximately 31,673.
Had an oil leak suddenly appear on the vehicle with only 55400 miles. Found there are technical service bulletins for this motor that the head cracks causing leaks. It is on many forums. Reached out to Mazda and got zero help
2018 Mazda CX5 2.5 ltr engine. Major oil leak that has been diagnosed as cracked or porous aluminum casting on the cylinder block. Oil is dripping consistently out of the problem area onto the manifold, causing smoke to flow into the cabin of the car and out of the hood as well. Car is currently at a Mazda dealership for a second diagnosis that confirmed the leak. Car is 3,000 miles out of warranty. Waiting to hear what the dealership is going to do. I also have contacted Mazda corp. and have a case# to take further action if needed. As you can see by the list of "engine" complaints for this problem, it is well documented that this is not an isolated issue.
Started 2018 Mazda CX-5 and the engine was extremely loud and a ticking noise was heard. Brought it to my local garage (Charlies Garage) and it was determined that the lifters needed replacement. Garage told me that Mazda issued a Service Alert on November 22, 2019 (Alert # SA-012/19) and did not notify customers of the Valve Tapping or knocking noise from cylinder head. The Garage then told me that Mazda issued a Technical Service Bulletin on April 23, 2020 (Bulletin No. 01-006/20). Again, customers were not notified of the Tapping Noise from Engine Bulletin that was issued. There were no alerts on the dashboard of the car, no warning lights, or other indicators. If Mazda had notified customers, the car would have been fixed UNDER WARRANTY. I do have a video of the noise and if you let me know how to send that, I will.
Car started leaking and burning oil. Blue smoke coming out of engine. Low oil pressure light went on. I had it looked at by an auto mechanic. This is a major safety issue as the engine will fail because of the low pressure. The car is not drivable. Turns out it's a known issue with the cylinder head that Mazda knows about because they issued a redesign and issued recalls for the 2019 and the turbo engine. They also issued a TSB for this problem. Car is out of warranty, but not old enough to have major engine issues.
I noticed a burning smell coming from engine. I took it to a Mazda dealership where they found a cracked cylinder head that needed complete replacing. There was no warning light or other symptoms before I noticed the smell. Vehicle has only been inspected by the dealership. Vehicle is out of warranty but only has 37000 miles on it.
Defective Engine. Cracked Cylinder Head. Engine oil leaked overnight because of known Mazda 2.5 liter Skyactive engine defect.
The issue began when I started to smell burning oil. As time went on smoke began to slowly come from the hood. I took my car to the mazda dealership and said that there was a cracked cylinder head in the engine. After doing research online this has been a major issue with the 2018-2020 model.
My 2018 Mazda CX-5 with just over 45,000 miles is showing the dreaded cracked cylinder head symptoms. Coolant is leaking causing a very noticeable burning smell in the cabin and faint smoke emanating from under the hood. My CX-5 has followed the maintenance schedule at the dealership that the vehicle was purchased. At this point the dealership has not been helpful at all. Mazda MUST start including 2018 CX-5s to CSP11 (covers 2019 CX-5s).
Cracked cylinder causes oil leak in 2018 Mazda CX-5. May occur in other model year CX-5 as well. Issue was inspected by an authorized dealer. Repair by Mazda not performed because vehicle was a few months past warranty expiration date. Issue with CX-5 cylinder-head are shown below: [XXX] [XXX] [XXX] INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)
I own a CX5 2018 Mazda with around 31,000 miles on it. Two days ago I experienced a smoke/fume event in my car while driving. The cabin filled with burnt oil fumes and a pungent smell. I happened to be near a Mazda dealership and was able to reach it with windows down and slow driving. The dealership inspected my car and confirmed a large oil leak caused by a cracked cylinder head. I was told this is a known issue with Mazda CX5/CX9 series and that it would be covered under warranty. Today I was informed by the same dealership that my standard powertrain warranty will not cover it, as it is 60,000 miles or 5 years. My car only has 31,000 miles on it, but it’s over the 5 years by little over a year. I am looking at paying around $6,500 out of pocket to fix my vehicle. I asked if there is an extended warranty from Mazda specifically regarding cylinder heads, due to this being a known defect, however the service person said there isn’t for my car. After some online research I did come across an extended powertrain warranty applying to 2019-2020 CX5 models due to the cylinder head cracking issues. I ask that this is being looked into and that the warranty needs to be extended to the 2018 model as well.
Replacement of cracked head cylinder diagnosis completed by Mazda dealer Fred beans in Willow Grove Pennsylvania Mazda is claiming they cannot cover the repair cost due to carfax not reporting all my maintenance services. After speaking to mazda customer service they confirmed that it is illegal to use carfax as documented proof. I provided proof of the maintenance aka oil change that was not eeported directly through carfax and have not heard anyrhing back. My car is under 60,000 miles and I have maintain my car and this should not be my fault this should not be my fault. Please help if possible i dont know who else to go to
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)
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
Cracked cylinder head at 65,0000 miles
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.
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.
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 $220.00. 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.
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.
Cracked cylinder head
Cracked cylinder head causing oil to leak
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