2018 Mazda CX-5 · symptom sheet
Check engine light or misfire
- 130owner reports
- 57,000median miles
- $5,100median quote
- 1involved a crash
Newest report Sep 24, 2026 · checked Oct 2, 2026
226 of the 350 complaints on this car are about the engine. 130 of those describe misfire, which makes it the most reported problem on the 2018 CX-5.
Tick what matches of 130 reports
Misfire on other CX-5 years
Report counts are for each model year on its own, so a newer car has had less time to collect them. Model years with too few reports of it for a sheet: 2014, 2015, 2016, 2017, 2020, 2021, 2026.
What this problem usually is
These reports start with the check engine light. Many describe the engine running rough or shaking at idle, a P0300-series code, or a catalytic converter code. A worrying number say the light was flashing. Owners often list ignition coils or spark plugs already replaced, and the light coming back afterward.
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.
The impeller inside the low-pressure fuel pump may crack and deform, potentially causing the fuel pump to fail.
A software error in the powertrain control module (PCM) may cause the engine to stall.
All 3 recalls on the 2018 Mazda CX-5, with the owner complaints on each recalled system
What owners paid
28 of the 130 reports quote a price. Each dot is one quote. The middle half runs $3,500 to $6,500.
When it happens
The middle half of failures fell between 43,000 and 75,896 miles, from the 65 reports that gave a mileage.
Is this a known problem?
The manufacturer has sent NHTSA 41 service bulletins or notices for the 2018 Mazda CX-5 that deal with this problem. Newest first.
Federal rules make a manufacturer send NHTSA a copy of any notice about a defect that goes to more than one dealer or owner. Most of these are service bulletins, the repair instructions manufacturers send to dealers. NHTSA generally leaves safety recall bulletins out of this file, and recalls are listed separately.
Subject: TSB 01-001/26 Warranty and Parts Kit Update INCLUDES: Warranty Extension Program - Special Service Program (SSP) D8 Check Engine Light ON with DTC P0126:00, 2018-2025 CX-5, 2019-2023 Mazda3, 2019-2022 CX-3, 2018-2021 Mazda6, 2020-2023 CX-30 Dear ...
Some customers may experience a check engine light ON with DTC P0126:00 (Thermostat stuck open) and one or more of the following symptoms: Engine takes longer to warm up. Engine temperature gauge fluctuates.
Some vehicles may display some (or all) of the following symptoms: • Check engine light on with DTC P061B • Light increase in engine rpms during acceleration • Transmission will not shift past 4th gear • Various U codes (U0401 ABS, U0401, U0415 FSC, U0301, ...
SSPD8 - Check Engine Light ON with DTC P0126:00 - WARRANTY EXTENSION For certain 2018-2025MY CX-5, 2019-2023MY Mazda3, 2019-2022MY CX-3, 2018-2021MY Mazda6, 2020-2023MY CX-30 that are equipped with the suspected coolant control valve, the warranty coverage ...
37 more on the 2018 Mazda CX-5 page.
What owners wrote
“Purchased vehicle from dealership drove 1650 miles, cylinder head began leaking, excessive oil. Took vehicle to repair shop their assessment cracked cylinder head. Warranty expired, dealership refused help in addition to Mazda Corp. unless brought to nearest dealership 140 miles away, with no guarantee. Vehicle is not driveable, I do have photos of the cracks.”
Filed Dec 19, 2024 · 1,650 miles
“2018 CX-5 has a cracked or porous (depending who is telling me the issue) cylinder head at 60000 miles. I was told by the Mazda service advisor that the issue is common. I reached out to Mazda for assistance in covering their faulty part and was told they would not cover any of it.”
Filed Nov 19, 2024 · 60,000 miles
“Vehicle has a cracked cylinder head at 43,000 miles. It is leaking oil and will lead to further engine damage if not repaired. Dealer inspected and diagnosed the problem. There were no vehicle warnings. It was brought to dealer because it was leaking oil and smelled of burning oil. It appears to be a common problem with Mazda Cx5s.”
Filed Oct 30, 2024 · 43,000 miles
“Cylinder head was found to be cracked for a while on the vehicle. This was discovered at 117K miles but likely was cracked well before judging from the age of the oil in the engine bay. Car has been maintained well this shouldn't be happening at all this early into its life.”
Filed Jul 31, 2024 · 117,000 miles
Should you keep driving it?
This page can't tell you that. 1 of 130 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. How reports land on this sheet.
Guide Which lights mean pull over now? Warning lights by color and urgency
Other problems on this car
- Engine leaks oil 63 reports
- Infotainment, screen or backup camera fails 46 reports
- Brakes grind, pulse or wear early 33 reports
- Burns oil or oil level rises 30 reports
- Engine stalls or loses power while driving 29 reports