2018 Mazda CX-5 problems

“My 2018 Mazda CX-5 Touring (2.5L non-turbo engine with cylinder deactivation) developed a burning oil smell that steadily worsened over several days. On XXX, at about 61,300 miles, I saw smoke coming from the engine compartment after driving. The engine had not overheated, and the car was regularly maintained. On XXX, an independent repair shop (A&M Auto Repair, [XXX] a large active oil leak. After steam cleaning the engine and removing the exhaust manifold, they found engine oil leaking from a hairline crack in the cylinder head, directly onto the hot exhaust manifold. The engine was also about one quart low on oil. The shop recommended replacing the cylinder head assembly, at a cost of about $5,700 before tax. Oil leaking onto the exhaust manifold is a fire hazard, and the smoke could reduce visibility for other drivers. Many other owners of 2018–2020 CX-5s with this engine have reported the same cracked cylinder head failure. I contacted Mazda Customer Experience (case number XXX) to request assistance. Mazda declined because the repair was diagnosed and performed by an independent shop rather than a Mazda dealer. I'm submitting this complaint so NHTSA can…”

“There has been numerous report of the Mazda CX 5 having failure rear differential. I just purchased a 2018 Mazda CX five for my daughter in September 2026 I now am experiencing this issue on the rear diff. The dealer will not cover the repair since it’s as is purchase Mazda should take this as a recall and fix the vehicle for the safety of the consumer.”

“The contact owns a 2018 Mazda CX-5. The contact stated that while his wife was driving at an undisclosed speed, there was smoke coming from under the hood. No warning light was illuminated. The contact's wife pulled over and discovered that there was oil leaking onto the ground. The vehicle was towed to the dealer, who determined that the #5 and #7 cylinder heads were cracked and needed to be replaced. The vehicle was not repaired. The manufacturer was made aware of the failure. The failure mileage was approximately 100,000.”

“I am reporting a safety issue involving engine failure and fumes entering the vehicle cabin as well as unintended braking post major engine repair at 75,000 miles on my 2018 Mazda CX5. My vehicle developed engine problems consistent with a cylinder head/coolant defect and began allowing fumes/smoke to enter the cabin while driving. This created a health and safety concern for occupants. I reported this to the dealership and was told the vehicle was safe to drive despite the presence of fumes in the cabin. A major engine repair was later performed. A few days following the repair, additional warning lights and system malfunctions appeared, including brake system warnings, and the vehicle later braked unexpectedly while driving nearly causing me to be rear-ended. The vehicle has been inspected by the dealership, but the root cause of the fumes and subsequent safety issues has not been clearly explained. This situation created a safety risk due to exposure to fumes inside the cabin and unexpected vehicle behavior while driving. Smoke/fumes video and any additional documentation can be provided upon request. Attaching the costly invoice as well.”

“Check engine light on when read it comes back with P0171 code”

“Touch Screen and/or infotainment center causing ghost touch. Available for inspection. Ghost touch (known Mazda issue) with touch screen has been changing radio stations, increasing volume to max. Will go into user settings and change guidance voice to full volume, increasing bass to full volume, fast forward songs, mute phone call feature, randomly switch from bluetooth to handset of phone. All of this is done without the driver or anyone else in the car touching anything. When this happens there is no easy fix. I cannot just stop the song, mute the volume. We have to wait for it to decide to stop and fix itself. It is a safety issue because You are driving and randomly volume goes to full blast an startles you, cannot hear what is going on around you, and hurts your ears. This is distracting and I have swerved my car because of it. Bluetooth capability is suppose to be handsfree, so if it keeps muting my call or switching to my phone, that is now a safety hazard as well. vehicle was inspected in 2021 by Mazda dealership. At that time they said the only thing they can do it remove the SIM card, and we would lose navigation. However the issue did not stop. It…”