2018 Mazda CX-9 Problems
Compared with other Mazda CX-9 years
Typical for this model
54/100 1.1× a typical year · 50 = typical
- Complaint rate is 1.1× that of a typical Mazda CX-9 year, weighted for crashes, fires, injuries, recalls and mileage, and allowing for the era and for how long each year has had to collect complaints.
- 11 of its 128 complaints were filed by the end of 2020.
- Most reported problem: Coolant leak from cracked cylinder head (73 complaints, median 82,040 mi).
- 2 recall campaigns on record. A VIN search at nhtsa.gov/recalls shows open recalls for a specific vehicle.
Nearby years with fewer complaints than typical and no open NHTSA investigation: 2015, 2016, 2017, 2019
Based only on NHTSA complaints, recalls and investigations. Not adjusted for how many vehicles were sold, and not a reliability rating. How this is calculated
- Complaints
- 128filed with NHTSA
- Median mileage
- 27,000miles, 16 complaints with mileage
- Recalls
- 2campaigns on record
- Trend
- RisingComplaints filed in the last 3 full calendar years are at least 25% higher than in the 3 years before.
- NHTSA crash rating
- 5 / 5stars overall, 2 rated versions
- EPA fuel economy
- 24 mpgcombined, 2.5L 4-cyl FWD · 22 city / 28 hwy
Sources: NHTSA records for the 2018 Mazda CX-9 (complaints, recalls, investigations), NHTSA crash tests, EPA fuel economy. Report an error
What owners report
Owner complaints for this model year are dominated by engine cooling problems: coolant loss traced to a cracked cylinder head on the 2.5T engine, often found by smell, a low reservoir or an overheating warning. A smaller but noticeable group of complaints covers the infotainment display developing corner cracks, and a handful describe sudden unintended braking or acceleration from the driver-assist and brake systems. Many engine reports come in between roughly 50,000 and 100,000 miles, though some arrive far earlier.
- Engine
Coolant leak from cracked cylinder head
- 73 complaints (57%)
- median 82,040 mi at 6.3 yrs old (4 state mileage, few)
- owner-quoted repair $9,800 (median of 9 quotes)
- filed 2022–2026
Owners describe losing coolant with no warning, sometimes noticing a sweet smell, condensation or a puddle, sometimes only a low reservoir or a brief temperature spike. In several cases the dealer confirmed a crack in the cylinder head and quoted cylinder head or full engine replacement; a number say the repair was not covered because the vehicle was out of warranty. Some complaints note that no low-coolant or check-engine light came on before the overheating message appeared, and owners point to a service bulletin for the symptom. Frequently reported between roughly 50,000 and 100,000 miles, though a few complaints describe under 40,000 miles and several above 120,000.
What to check: Ask whether the cylinder head or engine has already been replaced and whether the extended powertrain coverage for coolant leaks at the cylinder head applies to this vehicle. Check the coolant reservoir level and look for residue or a sweet smell near the back of the engine.
2 excerpts from owner complaints in NHTSA records
“A coolant leak appeared around 62,000 miles. Car started overheating and come to find that I had no more coolant left in the reservoir. I filled it back up and drove it to the mechanic, after almost a week in the shop and have been quoted over $2k for the fix. There is a TSB out on this issue. It is a known issue apparently from a casting defect in the heads / block.”
NHTSA complaint #11532749, filed 2023-07“Due to the flawed engine design which is well documented for these engines, ours started leaking coolant and it was eventually discovered that the head had cracked, and we were forced to have the head replaced. This repair cost us approximately $7600. Our hope is that Mazda will eventually issue a recall.”
NHTSA complaint #11595029, filed 2024-06 - Brakes
Unexpected braking or acceleration at low speed
- 16 complaints (13%)
- median 20,908 mi at 2.5 yrs old (10 state mileage)
- 3 mention a crash, fire or injury
- filed 2017–2026
Complaints describe the vehicle slowing or stopping on its own, sometimes with a smart brake or forward camera warning on the dash, and in other cases lurching forward while the brake pedal is held. Several owners say the car gave little or no warning before the intervention, and that restarting the vehicle cleared the message temporarily. Others report a hard or unresponsive brake pedal or an electronic parking brake that would not release. Reported across a wide mileage range, from under 11,000 miles to about 40,000 miles.
What to check: Ask the seller whether any forward-sensing camera or brake system software updates have been applied, and during a test drive note any warning messages or unexpected braking at low speed.
2 excerpts from owner complaints in NHTSA records
“I purchased a new Mazda CX-9 in sept 2017 because it had the highly touted smart city braking system for which I paid thousands extra. I had had a previous rear end collision and wanted to be sure this system would at least warn me. I set up some cardboard boxes wrapped in aluminum foil. I slowly (10 MPH) drove the car into them without touching the brake or accelerator. …”
NHTSA complaint #11053492, filed 2017-12, 946 miles“I was pulling into a parking spot in the upper parking lot at work. I stepped on the brake pedal so that I could stop and park but the pedal was hard and had no give. The car continued to roll forward over a curb and partly down a small set of stairs that go from the upper parking lot to the lower parking lot. The car stopped when it hit a metal railing and I shifted the car into park.”
NHTSA complaint #11296784, filed 2020-01, 35,000 miles - Electrical system
Cracks in the center infotainment display
- 12 complaints (9%)
- typically at 5.1 yrs old
- filed 2021–2025
Owners report hairline or spiderweb-like cracks appearing near the corners of the Mazda Connect display without impact, which spread over time and obscure the navigation, backup camera and other on-screen controls. Some say a dealer acknowledged the issue but that their vehicle was not included in the coverage offered for earlier model years, while others describe being offered only a partial credit toward a replacement unit. Reported from low mileage up to around 70,000 miles, often appearing within the first few years of use.
What to check: Inspect all corners of the center screen in daylight for hairline cracks and ask whether the display has been replaced or the infotainment warranty extension was applied to this vehicle.
2 excerpts from owner complaints in NHTSA records
“> I have a 2018 Mazda CX-9 with about 70,000 miles on it. Since 2020 this vehicle started developing cracks in the infotainment center screen. I only had about 23,000 miles on it at that time. the cracks are now starting to obscure my back up camera, communication system and nav system displays causing a safety issue. It is distracting to not be able to see clearly on this screen and I am afraid something will happen to me or my kids. …”
NHTSA complaint #11484377, filed 2022-09“The infotainment system screen has developed several cracks in the upper left-hand corner of the screen. Often time these cracks look like spiderwebs or frost --it's commonly referred to as spider cracking. This is the second time my vehicle has had this issue. At the present time, the cracks are contained to the upper left-hand corner of the screen, but they are getting larger. The vehicle has been inspected by my local MAZDA dealership and I'm awaiting a resolution. …”
NHTSA complaint #11510436, filed 2023-03
Buying note. Have a pre-purchase inspection focus on the cooling system and ask for documentation of any cylinder head or engine work, since that is the most frequently reported problem for this model year. Also confirm which open recalls and warranty extensions apply to the specific vehicle by VIN, and check the center display for cracks.
Summary written with AI from a sample of 60 NHTSA complaints for this model year (picked at random, with complaints that state a mileage and recent ones taken first), then checked automatically against the source records. Where a problem shows a complaint count, every complaint for this model year was matched with fixed keyword rules (written with AI and tested against the sample), and the mileage, age and repair figures are calculated from those complaints; owners' figures are as stated, not verified. Other counts refer to the sample. The excerpts come from NHTSA's public complaint records and are unverified; capitalisation is normalised, NHTSA staff notes are removed, and shortened text ends with “…”. Something wrong? Request a correction.
NHTSA recorded 128 consumer complaints for the 2018 Mazda CX-9. 16 of the complaints include a mileage, and 69% of those were filed for vehicles with under 50,000 miles; the median is 27,000 miles. Of all complaints, 4 involved a crash, 1 a fire, 2 an injury, according to the filers. NHTSA lists 2 recall campaigns and 470 technical service bulletins for this model year. Compared with the other 12 Mazda CX-9 model years that have at least 25 complaints and are old enough to compare, this one scores 54 out of 100, where 50 is a typical year for the model (typical for this model). The comparison allows for the era and for how long each year has had to collect complaints, but not for how many vehicles were sold.
Which parts are reported most
Complaints can name more than one part, so the counts add up to more than the total. Select a part to see its complaints, recalls and bulletins.
- Engine76 59%
- Other or unknown20 16%
- Electrical system15 12%
- Brakes11 8.6%
- Fuel system7 5.5%
- Steering3 2.3%
Also reported: Air bags (2), Engine cooling (2), Seats (2), Exterior lighting (1), Lane departure (1), Seat belts (1), Body and structure (1), Suspension (1).
Example complaints
Engine: “I was waiting in a stationary position, at a red light, behind some other vehicles, with my foot on the brake pedal. All of a sudden, the vehicle started to lurch forward as if someone had stepped hard on the gas pedal! I was struggling to keep the car still by depressing the brake pedal harder, but it wouldn't stop the car. I had to put it in park and turn off the engine to stop the forward thrust of the vehicle.”
NHTSA complaint #11232824, filed 2019-07, 11,000 milesOther or unknown: “Happened to me two times in past three weeks, where I am coming to a stop, or hardly moving, and car suddenly accelerates. Had my foot on the brake and the car was still trying to accelerate. Yesterday, 4/24/21 it took all my strength on the brake to keep the car from pulling into oncoming traffic. I have been driving for 39 years and have owned many cars, and something like this never happened to me. I will be bring the car dealership tomorrow, the car has only 10k miles on it as we don't do a lot of driving with it as we owe two cars. …”
NHTSA complaint #11413732, filed 2021-04, 10,300 milesElectrical system: “Car showed ignition on when the car was turned off. Same day while driving on highway car engine revved for no reason. Also when someone got out of parked car it said no key detected but car was still turned on and key was right beside me.”
NHTSA complaint #11233692, filed 2019-07, 18,500 milesTransmission and drivetrain: “my 2018 MAZDA CX-9 safety issue SCBS / SBS, LAS / LDWS, MASTER AND/OR HBC WARNING LIGHTS Forward sensing camera (FSC) stops functioning cause my car run rough even depress accelration and those light came on dashbaord -Forworad smart city brake support malfunction -smart brake system -front camera sensor malfunction”
NHTSA complaint #11685844, filed 2025-09Mileage when problems were reported
69% of the 16 complaints with a mileage were filed for vehicles with under 50,000 miles; the middle half falls between 11,000 and 65,000 miles.
Complaints by year filed
Trend: rising. Complaints filed in the last 3 full calendar years are at least 25% higher than in the 3 years before.
Crash test ratings
NHTSA's 5-Star Safety Ratings for the 2018 Mazda CX-9. Frontal results are shown driver / passenger; rollover shows the star rating and NHTSA's estimated risk of rolling over in a single-vehicle crash.
| Version | Overall | Frontal | Side | Side pole | Rollover |
|---|---|---|---|---|---|
| CX-9 · SUV AWD | ★★★★★ | 4 / 4 | 5 | 5 | 4 · 15.1% risk |
| CX-9 · SUV FWD | ★★★★★ | 4 / 4 | 5 | 5 | 4 · 15.9% risk |
Neighbouring years: 2019: same overall rating. A redesign between years can change both the car and the test.
Source: NHTSA New Car Assessment Program (5-Star Safety Ratings), nhtsa.gov/ratings.
Fuel economy and running cost
EPA ratings for each 2018 Mazda CX-9 version. Annual fuel cost is the EPA's estimate at its current fuel prices for 15,000 miles a year (55% city driving).
| Version | Engine | Transmission | City | Hwy | Comb. | Fuel / yr |
|---|---|---|---|---|---|---|
| CX-9 2WD | 2.5L 4-cyl | 6-speed automatic | 22 | 28 | 24 | $2,800 |
| CX-9 4WD | 2.5L 4-cyl | 6-speed automatic | 20 | 26 | 23 | $2,900 |
Source: U.S. EPA and Department of Energy, fueleconomy.gov. Ratings are for comparing vehicles; real-world mileage varies with driving and conditions.
Recalls and investigations
- 21V875000Nov 12, 2021Fuel system, gasoline › Delivery › Fuel pumpCovers: Mazda CX-9 2018–2019, CX-5 2018–2019, MX-5 2018–2019 +4 more
Mazda North American Operations (Mazda) is recalling certain 2018 Mazda3, Mazda6, 2019 CX-3, 2018-2019 MX-5, CX-5, CX-9, and 2019-2020 Mazda2 vehicles. The impeller inside the low-pressure fuel pump may crack and deform, potentially causing the fuel pump to…
- 19V403000May 30, 2019Electrical system › WiringCovers: Mazda CX-9 2018
Mazda North American Operations (Mazda) is recalling certain 2018 CX-9 vehicles. The wiring harness may disrupt electrical communications and disable the passenger frontal air bag, turn signals, and/or engine starting system.
Recall details for the 2018 Mazda CX-9 → · Check a VIN at nhtsa.gov/recalls
Technical service bulletins
TSBs are manufacturer notes to dealers about known repair procedures. They are not recalls and do not by themselves mean a vehicle has a fault. 470 on record; the latest 10 are shown.
- 11037899Sep 11, 2026Electrical system. 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…
- 11034447Jun 19, 2026Electrical system, Engine. 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…
- 11032003May 1, 2026Transmission and drivetrain. This bulletin supersedes the previously issued bulletin(s) listed below. The changes are noted in Red. 01-008/23 06/05/23 Some vehicles may exhibit rattling noises from the engine compartment and…
- 11032104Apr 30, 2026Body and structure, Other or unknown. DESCRIPTION Some vehicles may require the replacement of a damaged VIN plate or vehicle certification label. To obtain a replacement VIN plate (bulkhead-mounted and visible through the lower-left…
- 11032103Apr 21, 2026Engine, Brakes, Other or unknown, Transmission and…. This Service Alert supersedes the previously issued SA listed below: The changes are noted in Red. SA-011/24 02/12/24, 06/06/24, 07/29/24 DESCRIPTION Mazda has developed factory recommended…
- 11032101Apr 16, 2026Engine. 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…
- 11030636Mar 11, 2026Engine. 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…
- 11028133Jan 26, 2026Other or unknown. There are currently 2 methods for cutting a new auxiliary key blank. A. Auxiliary Key Trace Cut Method • B. Auxiliary Key Code Cut Method 2019 and newer models require a 10-digit key code to…
- 11028127Jan 5, 2026Other or unknown. Some customers may report an odor or water in the HVAC system and upon inspection, the cabin air filter may be found to be wet.
- 11026917Dec 17, 2025Electrical system. 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…
Other model years of the Mazda CX-9
| Year | Complaints | Median mi | Recalls | Crash ★ | MPG | Score (50 = typical) | Trend |
|---|---|---|---|---|---|---|---|
| 2023 | 13 | 12,100 | 0 | 5 | 23 | — | Too new |
| 2022 | 11 | 53,000 | 0 | 5 | 23 | — | Not enough data |
| 2021 | 40 | 51,093 | 1 | 5 | 24 | 50 · Typical | Rising |
| 2020 | 19 | 14,000 | 1 | 5 | 24 | — | Stable |
| 2019 | 53 | 26,500 | 2 | 5 | 24 | 31 · Fewer | Rising |
| 2018 | 128 | 27,000 | 2 | 5 | 24 | 54 · Typical | Rising |
| 2017 | 61 | 33,500 | 0 | — | 24 | 0 · Fewer | Rising |
| 2016 | 107 | 40,000 | 0 | — | 24 | 26 · Fewer | Rising |
| 2015 | 35 | 60,500 | 2 | 4 | 19 | 25 · Fewer | Falling |
| 2014 | 54 | 56,294 | 3 | 4 | 19 | 46 · Typical | Falling |
| 2013 | 68 | 55,011 | 4 | 4 | 19 | 67 · More | Falling |
| 2012 | 221 | 58,000 | 4 | — | 19 | 100 · More | Falling |
| 2011 | 171 | 74,000 | 4 | — | 19 | 93 · More | Falling |
| 2010 | 195 | 77,312 | 6 | — | 18 | 100 · More | Falling |
| 2009 | 59 | 85,000 | 6 | — | 18 | 41 · Typical | Falling |
| 2008 | 172 | 99,500 | 5 | — | 18 | 81 · More | Falling |
| 2007 | 86 | 94,000 | 5 | — | 18 | Not compared (before 2008) | Falling |
All Mazda CX-9 model years · Best and worst years by complaints
Frequently asked questions
What are the most common problems with the 2018 Mazda CX-9?
Owner complaints for this model year are dominated by engine cooling problems: coolant loss traced to a cracked cylinder head on the 2.5T engine, often found by smell, a low reservoir or an overheating warning. The issues reported most often: Coolant leak from cracked cylinder head; Unexpected braking or acceleration at low speed; Cracks in the center infotainment display.
How many NHTSA complaints does the 2018 Mazda CX-9 have?
NHTSA recorded 128 consumer complaints for the 2018 Mazda CX-9 as of Oct 27, 2026. Complaints are unverified consumer reports and may be duplicated or inaccurate.
What part of the 2018 Mazda CX-9 is reported most often?
Engine is named most often, in 76 complaints (59% of the total), followed by other or unknown with 20.
Has the 2018 Mazda CX-9 been recalled?
NHTSA lists 2 recall campaigns for this model year. To check a specific vehicle, enter its VIN at nhtsa.gov/recalls.
How did the 2018 Mazda CX-9 do in NHTSA crash tests?
NHTSA's 5-Star Safety Ratings give the 2018 Mazda CX-9 5 out of 5 stars overall, across 2 rated versions (body style and drive). Ratings from different model years are only comparable when the vehicle was not redesigned in between.
What gas mileage does the 2018 Mazda CX-9 get?
The EPA rates the 2018 Mazda CX-9 (CX-9 2WD, 2.5L 4-cyl) at 24 mpg combined, 22 city and 28 highway, with an estimated annual fuel cost of $2,800 at 15,000 miles a year. Other engine and drive versions are rated differently.
At what mileage are problems with the 2018 Mazda CX-9 reported?
Among the 16 complaints that include a mileage, the median is 27,000 miles and the middle half falls between 11,000 and 65,000 miles; 69% were filed for vehicles with under 50,000 miles.
About this data. Data from NHTSA (ODI) complaints, recalls, TSBs and investigations, updated Oct 27, 2026. Complaints are unverified consumer reports and may be duplicated or inaccurate. Crash ratings are from NHTSA’s New Car Assessment Program. Fuel economy is from the EPA and DOE (fueleconomy.gov).
Complaint counts come from NHTSA’s public complaint database; we count each complaint once. The source records for this vehicle are on nhtsa.gov. Scores and trends are our own summaries of that data, described in the methodology. This page is not legal, safety or repair advice: for a specific vehicle, check its VIN at nhtsa.gov/recalls and ask a qualified mechanic. See an error? Tell us.