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P0455 on Mazda CX-50

Evaporative Emission Control System Leak Detected (Gross Leak)

Factory diagnostic protocol and troubleshooting wire for fault code P0455 specifically for the Mazda CX-50 (2023–2026, 2.5L Skyactiv-G (187HP) / 2.5L Turbo (256HP) / 2.5L Turbo+ (320HP)).

Verified OEM Telemetry & Field Repair Tree
Mazda CX-502023–2026
Mazda CX-50
SUV2.5L Skyactiv-G (187HP) / 2.5L Turbo (256HP) / 2.5L Turbo+ (320HP)
Reliability
Sensor Voltage Ref
0.1V – 5.0V Ref
CX-50 SAE Mode $01
ECU Network Bus
500 kbps CAN-FD
ISO 15765-4 Compliant
Drivability Status
Drivable (Short Trip)
Low urgency level
Est. Repair Cost
$15 - $250 (DIY: $15 - $50)
Parts & Labor DIY
Check P0455 On Another Mazda Model:
Diagnose P0455 on Specific CX-50 Model Year:

1. Symptoms of P0455 on Mazda CX-50

When the Engine Control Module (ECM/PCM) on your Mazda CX-50 (2.5L Skyactiv-G (187HP) / 2.5L Turbo (256HP) / 2.5L Turbo+ (320HP)) logs fault code P0455, drivers commonly observe:

Check Engine Light on on Mazda CX-50 (2.5L Skyactiv-G (187HP) / 2.5L Turbo (256HP) / 2.5L Turbo+ (320HP))
Gas cap loose warning message on dashboard on Mazda CX-50 (2.5L Skyactiv-G (187HP) / 2.5L Turbo (256HP) / 2.5L Turbo+ (320HP))
Slight fuel vapor odor near rear of vehicle on Mazda CX-50 (2.5L Skyactiv-G (187HP) / 2.5L Turbo (256HP) / 2.5L Turbo+ (320HP))
Mazda CX-50 OBD-II Port Location
The 16-pin diagnostic connector is located Driver lower dash trim above footwell. Plug in your scan tool to verify freeze-frame sensor values.

2. Most Likely Causes on Mazda CX-50

Historical warranty claims and technical repair bulletins for Mazda CX-50 point to the following failure distribution:

55%
Missing, loose, or cracked gas cap seal (Mazda OEM Part)
25%
Faulty EVAP purge control solenoid (Mazda OEM Part)
12%
Stuck open EVAP vent valve (Mazda OEM Part)
8%
Cracked EVAP charcoal canister vapor hose (Mazda OEM Part)
* Source: Synthesized from NHTSA ODI field repair telemetry and verified OEM Technical Service Bulletin (TSB) repair tree frequency percentiles for Mazda CX-50.

3. Step-by-Step DIY Repair Guide for Mazda CX-50

01
Inspect and Tighten the Gas Cap

Remove gas cap, inspect rubber O-ring for cracks, tighten until it clicks 3 times. on the Mazda CX-50 equipped with 2.5L Skyactiv-G (187HP) / 2.5L Turbo (256HP) / 2.5L Turbo+ (320HP).

Required Tool: None
02
Replace Gas Cap with OEM Replacement

If the cap rubber is dried or cracked, replace with genuine OEM cap ($15). on the Mazda CX-50 equipped with 2.5L Skyactiv-G (187HP) / 2.5L Turbo (256HP) / 2.5L Turbo+ (320HP).

Required Tool: New OEM Gas Cap
03
Test EVAP Purge Solenoid Under Hood

Disconnect electrical plug and vacuum hose. Apply 12V; verify valve seals tight when unpowered. on the Mazda CX-50 equipped with 2.5L Skyactiv-G (187HP) / 2.5L Turbo (256HP) / 2.5L Turbo+ (320HP).

Required Tool: 12V Probe, Vacuum Pump
04
Inspect EVAP Canister Vent Valve Near Gas Tank

Check vent valve for road salt corrosion or spider nest clogs. on the Mazda CX-50 equipped with 2.5L Skyactiv-G (187HP) / 2.5L Turbo (256HP) / 2.5L Turbo+ (320HP).

Required Tool: Flashlight, Jack Stands
05
Smoke Test EVAP System

Pump mineral oil smoke into EVAP port to reveal any hairline cracked lines. on the Mazda CX-50 equipped with 2.5L Skyactiv-G (187HP) / 2.5L Turbo (256HP) / 2.5L Turbo+ (320HP).

Required Tool: EVAP Smoke Machine
Recommended Parts & Testing Tools

Equipment for Diagnosing Mazda CX-50 (P0455)

Prime Fast Delivery & Verified Fitment
EVAP Seal Replacement

OEM Tethered Fuel Gas Cap with O-Ring

4.7 / 5.0 (Direct Fit)

Tight-sealing factory fuel cap resolves common EVAP small/large leak codes without workshop visits.

$17 – $26 Prime
Check Fitment on Amazon
Sensor Signal Voltage Meter

AstroAI Auto-Ranging Digital Multimeter

4.6 / 5.0 (Best Seller)

Essential for testing 0.1V–5.0V sensor reference signals, ground continuity (<0.20Ω), and harness resistance.

$29.99 Prime
View on Amazon
Top Mobile OBD-II Scanner

BlueDriver Bluetooth Pro OBDII Scan Tool

4.7 / 5.0 (50,000+ Reviews)

Reads and clears enhanced codes (ABS, Airbag, Transmission, Engine) & live freeze-frame telemetry on phone.

Compare OEM & Aftermarket Replacement Sensors for Mazda CX-50Verified direct-fit pricing from Denso, Bosch, Motorcraft, and ACDelco on Amazon.
Find Parts on Amazon
* As an Amazon Associate, MazicBay earns from qualifying purchases. Prices & availability subject to change.

Other Common Fault Codes on Mazda CX-50

Frequently diagnosed powertrain, emissions, and sensor trouble codes logged on the Mazda CX-50:

4. Mazda CX-50 P0455 FAQs

What causes code P0455 to trigger on a Mazda CX-50?

On the Mazda CX-50 (2.5L Skyactiv-G (187HP) / 2.5L Turbo (256HP) / 2.5L Turbo+ (320HP)), P0455 is most frequently caused by Missing, loose, or cracked gas cap seal or Faulty EVAP purge control solenoid.

Where is the OBD-II port located on my Mazda CX-50?

On the Mazda CX-50, the 16-pin DLC diagnostic connector is located Driver lower dash trim above footwell. Plug in any standard OBD-II scanner with the ignition in the ON position to read freeze-frame parameters.

Can I safely drive my Mazda CX-50 with code P0455?

Yes. Completely safe to drive, but emissions test will fail. Given that P0455 carries a Low severity rating, we advise avoiding heavy towing or aggressive throttle inputs until sensor readings are verified.