2018 Mazda CX-9 · symptom sheet
Check engine light or misfire
- 51owner reports
- 68,000median miles
- $7,800median quote
- 0involved a crash
Newest report Jul 15, 2026 · checked Sep 9, 2026
94 of the 126 complaints on this car are about the engine. 51 of those describe misfire, which makes it the most reported problem on the 2018 CX-9.
Tick what matches of 51 reports
What got replaced
Few of these reports name the part that was replaced.
Recalls and investigations
2 recalls on the engine cover the 2018 model year. A recall on the same system isn't always the same failure, so read the defect text.
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 fail.
Risk and remedy
Remedy: Dealers will replace the fuel pumps, free of charge. Owner notification letters were mailed July 18, 2022. Owners may contact Mazda customer service at 1-800-222-5500 Option 4. Mazda's number for this recall is 5321K.
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.
Risk and remedy
Remedy: Mazda will notify owners, and dealers will repair the wiring harnesses, free of charge. The recall began July 26, 2019. Owners may contact Mazda customer service at 1-800-222-5500, Option 4. Mazda's number for this recall is 3419E.
What owners paid
6 of the 51 reports quote a price. Each dot is one quote. The middle half runs $6,800 to $11,000.
When it happens
The middle half of failures fell between 53,300 and 102,000 miles, from the 24 reports that gave a mileage.
What owners wrote
“Engine coolant leaks at cylinder heads I started noticing the problem at around 50000 miles its a small coolant leak but car is almost 6 years old and now 54000 miles”
Filed Mar 8, 2024 · 50,000 miles
“Engine coolant leaking due to cracked cylinder head, found by Mazda dealership service inspection and diagnostics. Powertrain warranty only covers this until 80,000 miles, our vehicle is 116,000.”
Filed Dec 21, 2023 · 80,000 miles
“We noticed a coolant leak and took vehicle in for service. Told that engine has a Coolant Leak at Cylinder Head [XXX] . 5 year old vehicle, 56k miles. No other warnings. All maintenance has been previously performed as required. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)”
Filed Oct 21, 2023 · 56,000 miles
“The cylinder head cracked and leaked engine coolant at 72K miles. This is a known design flaw IAW TSB 01-007/22. Vehicle overheated.”
Filed Sep 5, 2023 · 72,000 miles
Should you keep driving it?
This page can't tell you that. 0 of 51 reports involved a crash. Owners who file are the ones who had a bad experience, and nobody checks their reports. If the problem affects steering, braking, power or a fire risk, treat it as a safety fault and have it inspected before a long or high-speed drive.
File your own report with NHTSA. Complaint counts are how a problem gets an investigation.