2018 Mazda CX-9 problems

“While driving at highway speed in heavy rain the oil light suddenly came on followed within 30 seconds by an urgent need to immediately stop the car due to overheating. There was no radiator fluid left due to the sudden and catastrophic structural failure caused by a known manufacturing defect. Mazda calls it csp-11. They did NOT do a recall even though a situation such as this is clearly life-threatening. They offer an extended warranty to fix the problem fully up to 120,000 miles. Our car has 124,000 miles. Two months ago it would have been fully repaired at no cost but now they want in excess of 11 THOUSAND DOLLARS. I have spoken to more than 6 people in customer service, 2 supervisors, and they are ADAMANT they will not cover one single penny of repair even though this was not due to wear and tear, but due to a known and recognized manufacturing defect which they have since corrected in newer cars. First, this should have been a full recall since having this happen with no warning is without a doubt life threatening. If an inexperienced teenager had been driving and their engine suddenly seized, they likely would have died, and taken adjacent cars with…”

“The liftgate (trunk) opens sporadically. The system keeps trying to open the truck and it's causing a parasitic drain on my battery. I was stranded 2 hours from my home due to this. My trunk would sporadically beep three times, that is the only warning I received. There are safety recalls for other year of Mazda cx-9 but not my specific even though I am having the same issue.”

“My 2018 Mazda CX-9 with the SKYACTIV-G 2.5T engine has been diagnosed with a cracked cylinder head, cracked exhaust manifold, and cracked turbocharger at approximately 88,000 miles. This is a known design defect documented in Mazda TSB 01-002/23 and addressed by Customer Service Program CSP11, which extended the powertrain warranty to 10 years/120,000 miles for coolant leaks at the cylinder head. The TSB identifies exhaust manifold deformation and residual production stress as root causes of the cylinder head cracking. In my vehicle, the failure has extended to the exhaust manifold and turbocharger, both directly mounted to the cylinder head in the same high-stress zone. The turbocharger on this engine is a coolant-cooled unit. As coolant leaks from the cracked cylinder head, the turbocharger is deprived of its cooling supply, leading to excessive heat buildup and eventual cracking of the turbo housing. The turbo damage is a direct consequence of the cylinder head defect Mazda has already acknowledged. CSP11 covers the cylinder head but does not address consequential damage to the exhaust manifold and turbocharger caused by the same defect. I am requesting the…”

“My 2018 Mazda CX-9 experienced catastrophic engine damage after a radiator failure allowed coolant to enter the engine. The vehicle provided no dashboard warning, overheating alert, or coolant warning before the failure occurred. Modern vehicles are designed to alert drivers to overheating or cooling system failures. The lack of warning prevented me from addressing the issue and resulted in catastrophic engine damage. I believe this represents a potential safety defect in the vehicle’s cooling system monitoring and warning system.”

“- My 2018 Mazda CX 9 started stalling and jittering at idle and then eventually during slow driving. - Next day I got a check engine light, took to Mazda service center at the dealership I have been going to for last 6 years since I bought the car. - Service center diagnosed that there was a coolant leak through the cylinder head which seems to have cracked. - Further investigation indicated that this has been identified on many other similar Mazda engines and a Technical Service Bulletin had been issued by Mazda to Dealers. - On probing initially, dealership declined they were aware of any such problem. - The amount of repair for the engine replacement (cylinder head and other parts) is exuberant and is almost half of the value of my car, and is not expected for a low 44,000 miles car. - This had posed safety issue for my family since the stressed engine with leak in cylinder head could lead to fire and fatality. - I am awaiting response from Dealership and Mazda corporation case#[XXX] for a response especially when this issue has been filed under a class action lawsuit: [XXX]”

“I am submitting this recall request because my vehicle has experienced repeated incidents of a serious safety issue. While driving—most often on the highway—a warning appears that says “Smart System Brake Malfunction.” Immediately after, the car begins braking on its own without driver input. This has happened multiple times and, based on online reports, it appears to be affecting many Mazda vehicles across different models and years. Each time, I have been forced to pull over, turn off the car, and restart it to temporarily resolve the issue. This is extremely dangerous, especially at highway speeds, as it creates a high risk of rear-end collisions and sudden loss of vehicle control. When reported to Mazda, the concern was dismissed as a “sensor issue,” but the repeated nature and widespread reports suggest a potential systemic defect that requires urgent investigation and recall.”