Mazda CX-9 engine problems, 2016–2023
239 of the 429 complaints owners filed with NHTSA about the Mazda CX-9 2016–2023 name the engine (NHTSA’s “Engine” heading — the engine and its cooling system). The loudest years: 2018 (78), 2016 (70), 2017 (43). Filed under the same heading across these years: 4 manufacturer bulletins. Every figure is a linked federal record; none is a failure rate, none a repair cost, and none a verdict on one car.
Mazda CX-9 engine problems by model year
Source: NHTSA complaints, recalls, investigations and manufacturer communicationsOne row per model year on file, newest first. A year marked in depth has its own page: the complaints, the owners’ words and every document under this heading for that year.
| Model year | Complaints naming the engine | Share of the year’s | Typically at | On file under the heading | |
|---|---|---|---|---|---|
| 2023 | 0 | — | — | 42 TSBs | the year → |
| 2022 | 0 | — | — | 43 TSBs | the year → |
| 2021 | 20 | 51% | — | 99 TSBs | the year → |
| 2020 | 5 | 26% | — | 68 TSBs | the year → |
| 2019 | 23 | 43% | — | 87 TSBs | the year → |
| 2018 in depth | 78 | 61% | — | 106 TSBs | the record → |
| 2017 | 43 | 70% | — | 98 TSBs | the year → |
| 2016 in depth | 70 | 66% | — | 103 TSBs | the record → |
Two things the counts carry that are not the car: how many of each year were sold, and how long each has been on the road — an older year out-counts a newer one before anything is wrong with it. The share column is the honest comparison across years: what part of that year’s complaints named the engine. Nothing here is a rate.
When the engine complaints were filed, and at what mileage
Source: NHTSA complaint databaseFiled per calendar year, every model year together: 2017: 1 · 2018: 2 · 2019: 4 · 2020: 1 · 2021: 6 · 2022: 43 · 2023: 72 · 2024: 72 · 2025: 18 · 2026: 20
Across the model years, half of the 21 owners who gave an odometer reading reported the engine problem between 24,000 and 88,000 miles. A median of reports, not the life of a part.
In owners’ own words
Source: NHTSA complaint databaseFiled with NHTSA by the people who own these cars, about the engine, from the model years with the most to say. Quoted as written, with anything identifying removed; unverified reports — what was said, not a finding that it was true.
Driving the car home from work, the engine temperature gauge started to go up high. I added coolant that same night. Went to the dealership for a check up. I was told the coolant was coming out from the back of the engine and will need to partial repair the engine.
After owning this used vehicle for about 11 months, the engine temperature gauge indicated the car was running hot - about 240 degrees. After inspecting the vehicle at home, we added coolant to the system. This helped maintain engine temperature temporarily, but we noted over the next several weeks that the coolant was dropping rapidly.
2016 cx9, after reviewing online. Known issue with coolent and engine cylinder. Water coolent leak to engine head. Dealer asking 75k to replace engine. Mazda refused to acknowledge the known issue
On 04/21/22, I took my car to the dealer after noticing antifreeze on our garage floor and a burning smell. NO check engine lights had illuminated. They proceeded to tell me that there was a coolant leak from head/block and cavity leak (something about channel pressure).
Recently had my car into the local Madza dealer for oil change and break inspection. Soon after the oil change it started running rough. Then next thing I know it begins to overheat in the street at major intersection while driving home. Parked it let it cool down and then toed to Mazda dealer. Told antifreeze getting into the engine.
What is on file about the engine, across the years
Source: NHTSA recalls, investigations and manufacturer communications4 manufacturer bulletins filed under this heading, any model year
- Sep 4, 2026
- This Service Alert supersedes the previously issued service alert listed below. The changes are noted in Red text. SA-038/26 06/15/26 DESCRIPTION Some customers may complain about any of the following: 1. Infotainment Center Display does not provide the Authorization Code (OTP) during the MyMazda App Connected Vehicle enrollment. 2. Remote functions inoperative. Engine Start / Stop Door Lock / U
- Jun 19, 2026
- This SA supersedes the previously issued SA(s) listed below. The changes are noted in Red. SA-061/25 12/17/25 DESCRIPTION If you encounter any type of electrical concern (e.g, dead battery, engine no start, DTC(s) stored...), interview the customer before proceeding with normal MGSS diagnosis by asking if any aftermarket devices have been installed. Aftermarket devices may be the cause of the elec
- Apr 16, 2026
- This Service Alert supersedes the previously issued M-Tip(s) listed below. The changes are noted in Red text. MT-002/19 09/30/19 and 12/19/19 DESCRIPTION If an engine assembly is replaced after a catastrophic internal mechanical failure, clean the intake manifold internally before installing a replacement engine assembly. If the intake manifold is not cleaned properly, the replacement engine may f
- Mar 11, 2026
- This Service Alert supersedes the previously issued SA(s) and TSB(s) listed below: The changes are noted in Red. SA-035/24 05/31/24 DESCRIPTION There is a concern that some water pumps are being replaced that are not faulty, due to signs of a very small coolant leak from the bleed hole. This Service Alert is to inform you about the water pump sealing mechanism and the criteria if replacement is ne
Every one filed under the heading is listed. Quote the document number at a service desk — it is a diagnosis the maker has already written down.
Common questions
Source: NHTSA complaint database, recalls and manufacturer communicationsWhich Mazda CX-9 years have the most engine complaints?
2018, 78; 2016, 70; 2017, 43. Raw counts, and an older year has had longer to collect them; by share of each year's own complaints the loudest is the 2017 (70%).
Is there a recall for the engine on the Mazda CX-9?
No recall campaign is filed under this heading on any of these model years. A bulletin is not a recall: it carries no federal duty to repair for free.
When do engine problems show up on the Mazda CX-9?
Owners who gave an odometer reading reported it at a median of 53,186 miles across the model years; half of them between 24,000 and 88,000. That is when reports cluster, not the life of a part.
What does NHTSA's "Engine" heading cover?
The engine and its cooling system. Owners choose the heading when they file, so it says which area of the vehicle the complaint is about, not which part failed.