2019 Mazda CX-9 problems

“We recently noticed a coolant smell upon cold start up of our 2019 Mazda CX-9 Signature. Upon further investigation, we found that there is a Service Bulletin (TSB-01-013/21) issued by Mazda for a manufacturer's defect in the cylinder head causing coolant leaks into and around the exhaust manifold. This is a known and widespread issue, but our car's warranty has lapsed due to mileage (187K miles).”

“The contact owns a 2019 Mazda CX-9. The contact stated that a State Inspection was performed on the windshield for cracks. The contact stated that while driving in the rain, the front windshield wipers turned on independently with the switch in the off position. The contact was unable to turn off the windshield wipers. The contact pulled over to the side of the road and turned off the vehicle. When the vehicle was restarted, the front windshield wipers had turned off. The contact stated that the failure persisted and worsened. The contact stated that occasionally the windshield wipers failed to turn off. The vehicle was taken to the dealer; however, no cause for the failure was found. The vehicle was not repaired. The contact purchased and replaced a sensor. Upon investigation, the contact became aware that the on and off switch for the front windshield wipers related to the sensor located on the front windshield. The contact stated that the sensor controlled the on and off switch and failed to function as intended. The contact stated that the OEM windshield provided protection against the sensor malfunctioning; however, if the front windshield was replaced…”

“The engine cylinder head developed an internal coolant leak, allowing coolant to enter the combustion chamber. This caused engine overheating and smoke coming from the tailpipe while driving. A dealer performed a coolant pressure test confirming coolant leaking into the combustion chamber, and wet/dry compression testing on all 4 cylinders showed low and inconsistent readings consistent with cylinder head coolant intrusion (Cylinder 1: 105/125 psi, Cylinder 2: 115/125 psi, Cylinder 3: 110/175 psi, Cylinder 4: 160/190 psi). Overheating creates a risk of sudden loss of power and potential engine failure while driving, including on the highway. The problem has been confirmed and diagnosed by an authorized dealer service center, and the manufacturer's technical hotline department reviewed the diagnostic findings directly. Warning symptoms (overheating codes and visible tailpipe smoke) first appeared at the time the vehicle was brought in for diagnosis. The manufacturer has an active technical service bulletin addressing cylinder head coolant leaks on this engine and model, along with a related warranty extension program, but has denied coverage for this repair on…”

“I am reporting a serious safety issue involving a defective suspension part (lower control arm) manufactured by Dorman and purchased from an online auto parts retailer. On October 7, 2024, I ordered a Dorman lower control arm for my vehicle and had it professionally installed on November 7, 2024 at Johnston and Magwood Wheels & Tires. On November 8, 2024, at approximately 5:40 p.m., while I was driving and made a hard brake, I suddenly lost steering control and my front left wheel collapsed. Fortunately, I was the only one in the car and managed to avoid an accident. My vehicle had to be towed to a nearby shop (Kal Tire) and was later sent back to the original shop for further inspection. On November 12, technicians confirmed that the newly installed lower control arm had failed, which caused serious damage to the suspension. I paid $1,774.10 in repairs in order to make the car safe to drive again. This is extremely dangerous — if I had been driving on a highway or with passengers, it could have resulted in a major accident or injuries. When I contacted the retailer about the warranty, they only offered to refund the part itself and refused to take…”

“I was backing out of a parking spot while watching the backup camera when I felt a bump as if I hit something but the camera was showing I have enough space to the cars behind me. It turns out the backup camera image was frozen on the display and I had hit a car parked behind my car. Please investigate and make the manufacturer solve problems with the hardware or the software. Make sure the display shows a warning when the camera fails and the vehicle drives backwards. There may be children behind the car. Shifting into park and then into reverse again caused the camera to work correctly.”

“The contact owns a 2019 Mazda CX-9. The contact stated while driving 65 MPH on the interstate, the passenger’s side rear wheel well trim molding detached. The vehicle was taken to a local dealer and the contact was informed that the wheel well trim molding would be replaced. The parts were not yet available and the vehicle was not repaired. The manufacturer was made aware of the failure. The failure mileage was 21,820.”