AutoUtility currently tracks 126 official NHTSA owner defect complaints for the 2018 Mazda CX-9. Engine & Cooling issues are the most frequently reported category, appearing in 73 complaints (57.9% of submitted records). Among these NHTSA complaint records, 4 filings cite a crash, 1 cites a fire, 2 report one or more injuries.

Key Problem Findings
  • Total NHTSA Complaints: 126 reports
  • #1 Reported Problem Area: Engine & Cooling (73 reports • 57.9% of submitted complaints)
  • Secondary Problem Areas: Electrical System (15), Powertrain & Transmission (13)
  • Crash-Citing Complaints: 4 filings
  • Fire-Citing Complaints: 1 filings
  • Complaints Reporting Injuries / Fatalities: 2 injury filings • 0 fatality filings
Reporting Methodology: Statistics describe unverified consumer submissions voluntarily filed with NHTSA. Complaint volume is not normalized for vehicle sales volume or miles driven. Multiple components can be cited within a single owner complaint submission.
Total Complaints
126
Submitted to NHTSA ODI
Crash-Citing Complaints
4
Filings citing a collision
Fire-Citing Complaints
1
Filings citing smoke or fire
Complaints Reporting Injuries
2
Filings citing one or more injuries
Complaints Reporting Fatalities
0
Consumer filings citing fatalities

Most Reported Problems for 2018 Mazda CX-9

Top automotive subsystem defect categories ranked by unique owner complaint volume in federal records

#1 Problem Area 57.9% of complaints

Engine & Cooling

73 owner complaints submitted to NHTSA ODI
✓ 0 crashes or fires cited
#2 Problem Area 11.9% of complaints

Electrical System

15 owner complaints submitted to NHTSA ODI
⚠️ NHTSA Recall Context

NHTSA records list 1 official safety recall campaign for this model year involving the same broad component area:

*Component overlap means an official recall exists for the same broad vehicle system. It does not establish that an individual owner complaint was caused by, covered by, or resolved through that recall.
🔥 1 fire report
#3 Problem Area 10.3% of complaints

Powertrain & Transmission

13 owner complaints submitted to NHTSA ODI
✓ 0 crashes or fires cited
#4 Problem Area 8.7% of complaints

Brakes & Traction Control

11 owner complaints submitted to NHTSA ODI
⚠️ 2 crash reports 🩹 1 injury report entry
#5 Problem Area 5.6% of complaints

Driver Assistance & Safety Tech

7 owner complaints submitted to NHTSA ODI
✓ 0 crashes or fires cited
Domain Share Note: Share percentage represents the proportion of unique complaint filings referencing each vehicle system. Because single complaints may cite multiple systems (such as engine and electrical simultaneously), domain percentages represent individual category incidence and may sum to over 100%.

Symptoms Mentioned in NHTSA Owner Reports for 2018 Mazda CX-9

Specific mechanical, electrical, and driver-assist defect symptoms identified via deterministic narrative analysis

AutoUtility uses deterministic phrase matching to identify recurring symptom descriptions within consumer-submitted NHTSA complaint narratives.

Engine & Cooling 24.6% of complaints

Engine Coolant Intrusion / Oil Leak

31 complaint narratives describe this symptom
Engine & Cooling 3.2% of complaints

Engine Overheating / Temperature Warning

4 complaint narratives describe this symptom
Symptom Identification Method: A complaint may describe more than one symptom, so percentages may sum to more than 100%. Symptom identification reflects text contained in consumer-submitted complaint records and does not establish a confirmed mechanical diagnosis.

Recent NHTSA Owner Reports for 2018 Mazda CX-9

Representative defect filings submitted by owners to the NHTSA Office of Defects Investigation

Engine & Cooling NHTSA ODI ID: #11755628
Filed: 08/08/2026

"I was driving home from work and may car started overheating out of nowhere. I was stuck in traffic and white smoke was exiting my exhaust. I pulled over and all of my coolant leaked out of my car. Took it the shop and they said I had a cracked head and need a whole new engine. I seen that there..."

Incident Date: 07/29/2026 • Raw NHTSA Component: ENGINE
Engine & Cooling NHTSA ODI ID: #11750583
Filed: 07/15/2026

"The cylinder head on this 2018 Mazda CX-9 (Skyactiv-G 2.5T engine) cracked, allowing engine coolant to leak and intermix with engine oil, causing loss of coolant and catastrophic engine failure. The vehicle became undriveable in the first week of November 2025 at approximately 125,019 miles and has..."

Incident Date: 11/25/2025 • Raw NHTSA Component: ENGINE
Seats & Interior NHTSA ODI ID: #11742848
Filed: 06/08/2026

"My passenger heated seats malfunction while I was driving. As I was driving on the highway I smelled something burning. I didn't know where the smell was coming from it was strong . Then while I'm driving on the highway my seat started to smoke a lot I got scared and pulled on side of the road. I..."

Incident Date: 02/13/2026 • Raw NHTSA Component: SEATS
Engine & Cooling NHTSA ODI ID: #11742255
Filed: 06/05/2026

"My wife was driving the vehicle when the emergency lights started going off. She had to pull over because the car wouldn't run and said it was overheated. All the maintenance has been done to the car. We took it to the dealership and they said it is a cracked head and it is a known issue. They even..."

Incident Date: 05/20/2026 • Raw NHTSA Component: ENGINE
Powertrain & Transmission NHTSA ODI ID: #11731137
Filed: 04/14/2026

"My 2018 Mazda CX-9 with the SKYACTIV-G 2.5T engine has been diagnosed with a cracked cylinder head, cracked exhaust manifold, and cracked turbocharger at approximately 88,000 miles. This is a known design defect documented in Mazda TSB 01-002/23 and addressed by Customer Service Program CSP11,..."

Incident Date: 04/01/2026 • Raw NHTSA Component: POWER TRAIN
Consumer Narrative Notice: Excerpts are sanitized text descriptions submitted by vehicle owners to the federal ODI database. They reflect the reporting consumer's observations at the time of filing and have not been independently confirmed by vehicle manufacturers or government investigators.

Complaint History for Mazda CX-9

Reported defect complaint volume across sibling model years (2015–2026)

Model Year NHTSA Complaints Crash Reports Safety Recalls Detailed Report
2015 Mazda CX-9 35 1 2 View 2015 Problems →
2016 Mazda CX-9 99 3 0 View 2016 Problems →
2017 Mazda CX-9 61 0 0 View 2017 Problems →
2018 Mazda CX-9 Current Page 126 4 2 Current
2019 Mazda CX-9 53 1 2 View 2019 Problems →
2020 Mazda CX-9 19 1 1 View 2020 Problems →
2021 Mazda CX-9 37 7 1 View 2021 Problems →
2022 Mazda CX-9 9 1 0 View 2022 Problems →
2023 Mazda CX-9 12 3 0 View 2023 Problems →
2024 Mazda CX-9 0 0 0 View 2024 Problems →
2025 Mazda CX-9 0 0 0 View 2025 Problems →
2026 Mazda CX-9 0 0 0 View 2026 Problems →
Comparative Disclaimer: Complaint totals are unadjusted historical counts and are not normalized for vehicles sold, active fleet size, or total road mileage. Newer model years naturally have had less calendar exposure time to accumulate owner filings.

Detailed NHTSA Component Breakdown for 2018 Mazda CX-9

Complete distribution of consumer defect reports across all 35 granular NHTSA system and subsystem classifications

Vehicle Component / System Total Complaints Crash Reports Fire Reports Reported Injury Entries Reported Fatality Entries
Engine NHTSA category: ENGINE 58 0 0 0 0
Other / Uncategorized NHTSA category: UNKNOWN OR OTHER 11 1 0 0 0
POWER TRAIN,ENGINE 8 0 0 0 0
Electrical System NHTSA category: ELECTRICAL SYSTEM 6 0 1 0 0
Service Brakes NHTSA category: SERVICE BRAKES 4 1 0 0 0
ENGINE,FUEL/PROPULSION SYSTEM 3 0 0 0 0
Powertrain NHTSA category: POWER TRAIN 3 0 0 0 0
ELECTRICAL SYSTEM,UNKNOWN OR OTHER 2 0 0 0 0
Engine & Cooling NHTSA category: ENGINE AND ENGINE COOLING 2 0 0 0 0
Fuel System NHTSA category: FUEL SYSTEM, GASOLINE 2 0 0 0 0
Seats & Restraints NHTSA category: SEATS 2 0 0 0 0
Visibility & Wipers NHTSA category: VISIBILITY/WIPER 2 0 0 0 0
Air Bags NHTSA category: AIR BAGS 1 1 0 1 0
AIR BAGS,SERVICE BRAKES,VISIBILITY/WIPER 1 1 0 1 0
ELECTRICAL SYSTEM,BACK OVER PREVENTION 1 0 0 0 0
ELECTRICAL SYSTEM,CHILD SEAT 1 0 0 0 0
ELECTRICAL SYSTEM,ENGINE 1 0 0 0 0
ELECTRICAL SYSTEM,LANE DEPARTURE,BACK OVER PREVENTION 1 0 0 0 0
ELECTRICAL SYSTEM,SERVICE BRAKES,FORWARD COLLISION AVOIDANCE 1 0 0 0 0
EXTERIOR LIGHTING,SERVICE BRAKES,FORWARD COLLISION AVOIDANCE 1 0 0 0 0
Fuel & Propulsion System NHTSA category: FUEL/PROPULSION SYSTEM 1 0 0 0 0
POWER TRAIN,ELECTRICAL SYSTEM,SERVICE BRAKES 1 0 0 0 0
Seat Belts NHTSA category: SEAT BELTS 1 0 0 0 0
SERVICE BRAKES,ENGINE 1 0 0 0 0
Steering NHTSA category: STEERING 1 0 0 0 0
STEERING,ELECTRICAL SYSTEM 1 0 0 0 0
STEERING,POWER TRAIN,ENGINE 1 0 0 0 0
Structure & Body NHTSA category: STRUCTURE 1 0 0 0 0
Suspension NHTSA category: SUSPENSION 1 0 0 0 0
UNKNOWN OR OTHER,BACK OVER PREVENTION 1 0 0 0 0
UNKNOWN OR OTHER,ENGINE 1 0 0 0 0
UNKNOWN OR OTHER,FORWARD COLLISION AVOIDANCE 1 0 0 0 0
UNKNOWN OR OTHER,FUEL/PROPULSION SYSTEM 1 0 0 0 0
UNKNOWN OR OTHER,SERVICE BRAKES,ENGINE 1 0 0 0 0
UNKNOWN OR OTHER,SERVICE BRAKES,FORWARD COLLISION AVOIDANCE 1 0 0 0 0
Data Attribution & Reporting Methodology: Complaints are unverified voluntary submissions to the NHTSA Office of Defects Investigation (ODI). Because multiple vehicle components can be cited within a single owner complaint submission, component-level rollups may sum to more than the unique complaint count (126). Injury and fatality entries in the detailed table reflect raw values entered by reporting consumers across individual submissions; they are not deduplicated casualty statistics and may include duplicate or unverified entries. Complaint volume is not normalized for sales volume or vehicle mileage and does not represent an audited component failure rate.
Official US Government Data Provenance

The complaint records on this page are retrieved directly from the NHTSA Office of Defects Investigation (ODI) public database.

Local Production Store Compiled: August 2026 • Deterministic Audited Dataset • Zero Dynamic External API Runtime Latency.