2016 MAZDA CX-9 Complaints

The cylinder head (which involves the engine cooling system) has a known manufacturer defect that affects all year/models of the Mazda CX-9 with turbo. The manufacturing defect poses a risk to motor vehicle safety in a group of vehicles or equipment of the same design and/or manufacturer. Specifically, the overheating and failure of the engine can occur at any time, without warning. This puts my family at risk of being stranded on a roadway, particularly because my car is often driven in rural areas. The manufacturing defect is significant and is acknowledged by Mazda: Mazda has offered owners a voluntary, limited, warranty extension (CSP11) of 10 years or 120,000 miles. The voluntary warranty extension is not sufficient because it is limited in duration while the safety risk can happen at any time after the warranty extension expires. The warranty extension essentially only applies to about half of the expected lifetime of the car. NHTSA should determine that a recall and repair should be issued by Mazda that does not expire. The engine is defective, poses a safety hazard, and Mazda has fixed the engine for subsequent models (starting in 2021), so a repair is available.

I own a 2016 Mazda CX9 Touring FWD (180k miles). Today my car was diagnosed with cracked cylinder head, resulting in coolant and oil leak from the head gasket. While there is a class action settlement about it where Mazda accepted the manufacturing defect, they do not cover the engine repair/cylinder head replacement because my car's mile is over 120k. If it is a manufacturing defect, why year/mile make a difference on the responsibility of the manufacturer? Mazda obviously sold defect vehicles to their customers, and driving these vehicles under this condition is very dangerous! Now, they are expecting me to pay more than $10,000 for a vehicle priced around $6,000!

In June of 2022 I started having a strong antifreeze/engine coolant smell inside the cab of my vehicle and also outside the vehicle. I had the car checked for a radiator leak, but there wasn’t one. I took my car into my local Mazda where they found that the engine coolant was leaking into the heads of the engine. Mazda kept my car for 5 months and repaired the problem, it cost me $4000 and they had added a 12 month 12,000 mile warranty for the parts. My car is a 2016 Mazda cx-9 at the time of the repair it had 70,430 miles on it. Now a few years later I am having the same issue with the coolant smell inside the cab and outside my vehicle, it goes into the shop for diagnosis on Monday November 10,2025. The car now has 118,000 miles on it. I had purchased an extended warranty for the car at the time of purchase but it had timed out a month before I took my car in for the first repair….please Mazda stand behind your vehicles I am a senior woman with very little income and I will not be able to pay out of pocket for this repair and I CANNOT afford a new car… I would like to get reimbursed for my out of pocket on the first repair and get my car repaired this time as well under a warranty.

Cylinder head crack. Combustion gasses leaking into coolant causing overheat. Combustion gasses bleeding into oil causing excessive crankcase pressure.

The contact owns a 2016 Mazda CX-9. The contact stated that while driving approximately 45-50 MPH, the vehicle suddenly lost motive power with white smoke coming from the front of the vehicle. The contact was able to get to the side of the road to inspect the vehicle and became aware that there was coolant splattered all over the engine compartment. The failure had occurred twice. The “WRENCH” symbol was displayed with the “Service Vehicle” message displayed. The vehicle was taken to the dealer, who diagnosed that the coolant pump and water pump were leaking, and the radiator needed to be replaced. The vehicle was not repaired. The manufacturer was made aware of the failure. The manufacturer opened for the failure. The failure mileage was approximately 148,000.

Smart City Break Malfunction warning light appears while driving. Simultaneously the tire pressure warning appears. Also, at the same time, the temperature reads -20 to -40 degrees. Yes, vehicle is available for inspection. Fearful that car could randomly break while driving putting myself and family in danger since there is a malfunction. Mazda service center says the problem can’t be reproduced so there’s nothing they can do. The problem seems to appear when the outside temperature is 60 degrees Fahrenheit or higher.

Head gasket leaking and caused major engine issue at 89,000 miles. Mazda has known of this issue, but refuses to recall it.

While my wife was driving her 2016 Mazda Cx-9 Grand Touring on the freeway, many of the dashboard indicator lights came on warning her the engine was over heating and to pull over immediately. While she was attempting to move over to the shoulder, smoke appeared from underneath the engine hood which made it difficult to safely move over to the shoulder. She believed the car was on fire so immediately exited the vehicle along with her sister whom was pregnant. I arrived within minutes and noticed the engine compartment was smoking and coolant/engine oil leaking underneath the car. The car was towed to my local Mazda dealership where I was advised days later the engine needed to be replaced due to blown head gaskets. They advised the vehicle over heated causing oil and coolant leaking from cylinder head that is warped. This repair would cost $11, 179.29. Mazda service advisor also mentioned the radiator and lower/upper radiator hoses needed to be replaced. This repair would cost $2691.28. This incident could've resulted in serious injuries or death from a known issue with these engines by Mazda. It's only a matter of time before this failed engine turns into a fatality. Do the right thing Mazda and fix these engines. Your reputation is on the line.

Sudden and dramatic loss of engine coolant. Received a warning that engine was overheating, and to shut off engine. Quickly obeyed the prompt and found that most of the engine coolant had been lost due to a catastrophic failure of either the head gasket or head itself.

Vehicle failed to turn off the engine while in park and I was unable to lock vehicle while engine was still running. The ignition button failed to work.