Problems · NHTSA complaints

2016 Mazda CX-9 problems

Owners filed 99 complaints about the 2016 Mazda CX-9 with NHTSA between Aug 2016 and Nov 2025. The most-cited component is engine (61).

Complaints
99
Filed with NHTSA
Crashes
3
Reported by owners
Fires
1
Reported by owners
Injuries
3
People reported injured
Deaths
0
Reported to NHTSA
01 —By component

Complaints by component

One complaint can cite several components
  1. Engine61
  2. Electrical system14
  3. Service brakes11
  4. Power train9
  5. Fuel/propulsion system7
  6. Structure4
  7. Seats3
  8. Vehicle speed control3
  9. Wheels3
  10. Forward collision avoidance2
  11. Steering2
  12. Engine and engine cooling2
  13. Suspension2
  14. Air bags2

Complaints are unverified owner reports to NHTSA and are not normalized for sales volume. One complaint can cite several components.

Data from NHTSA Complaints API · synced Oct 28, 2026NHTSA vehicle page
02 —Trend

When complaints were filed

Does it get worse with age? Complaints per calendar year filed
View as table
Model yearComplaints filed per calendar year
20162
20173
20187
20198
20205
20216
202223
202317
202426
20252

Mileage at failure isn’t a structured field in NHTSA complaint data, so we don’t chart it. Some owners mention it in their reports below.

03 —Owner reports

Top problems in owners’ words

Verbatim from NHTSA complaints, newest first

Engine

61 reports1 crash
“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…”
Owner complaint to NHTSAFiled Nov 3, 2025EngineODI 11697196

Electrical system

14 reports1 crash1 fire
“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.”
Owner complaint to NHTSAFiled Apr 23, 2025Electrical system, Forward collision avoidanceODI 11656449

Service brakes

11 reports
“The vehicle has tire pressure monitoring system malfunction warnings and parking brake malfunction warnings even after taking to dealership to be fixed. Was told it’s a known problem by Mazda, should be recalled, but there were not any current recalls for the issue.”
Owner complaint to NHTSAFiled Dec 11, 2023Wheels, Service brakesODI 11559545

Power train

9 reports
“August 2nd I noticed a smell of Coolant coming from my car. I looked under my car and noticed it leaking green coolant. I took it to Mazda where they had it for 7 days to then give me a $6,300 estimate with possible added expenses. They diagnosed it as a cracked cylinder head and needs a gasket as well. I am a single mother and have work but I cannot afford that repair especially since Mazda is not going to honor there vehicle and what they stand by. With this issue with the coolant leak and the cracked cylinder the vehicle could have overheated and go into limp mode and come to a sudden stop with my children in the car while driving on the road. I could be hit as this puts my family at risk of injury while we go to school or work. Mazda has done nothing but tell me to submit a claim with customer service which I have. I had my case manager call me once and left a voicemail and I have called multiple times and have not heard back. There was no warning of this until I found forums and other stories that this unfortunately has happened to hundreds of Mazda owners.”
Owner complaint to NHTSAFiled Aug 27, 2024Power train, EngineODI 11611282

Fuel/propulsion system

7 reports
“Vehicle “surges” at idle. 300-500 RPMS at a time. Sometimes the brakes hold and sometimes not. Have nearly been in 3 collisions the last 2 days because of this issue. The ECM codes indicate throttle body or TPS issue, both of which have been unfounded. Vehicle has 63,000 miles. Researching this topic online found that many others have had this issue with no associated safety recalls noted. I am hoping to bring light to this so someone doesn’t have to be injured or killed to have this rectified.”
Owner complaint to NHTSAFiled Mar 4, 2024Vehicle speed control, Engine, Fuel/propulsion systemODI 11575368

Structure

4 reports1 crash
“Engine Coolant Leaking from rear of engine near Exhaust / turbocharger at Cylinder Head. No Warning Lights indicating problem until coolant level low causing overheating and fire risk. Rear Brakes not releasing completely from "City Mode" where brakes are kept close to rotor "to increase braking response in City driving" - causes premature brake wear, warped brake rotors (reoccurs within 10K miles from new / replaced rotors) Front Bumper Fascia keeps coming loose at clips near headlights on both Driver and passenger side. Had replaced at dealership 3 times, but continues. Bumper coming loose and can obstruct headlights while moving around at highway speeds”
Owner complaint to NHTSAFiled Aug 21, 2022Structure, Service brakes, EngineODI 11480443
Data from NHTSA Complaints API (owner reports, unverified) · synced Oct 28, 2026

Complaints are unverified owner reports to NHTSA and are not normalized for sales volume. One complaint can cite several components.