Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
2021 Acura TLX BaseFACTORY OEM SERVICE PROCEDURE
DTC Troubleshooting: P0456(3.0L Engine): Notes
DTC P0456 : Evaporative Emission (EVAP) System Very Small Leak Detected
Special Tools Required
Vacuum Pump/Gauge, 0-30 inHg Snap-on YA4000B or equivalent, commercially available
NOTICE:
- Before you troubleshoot, review the How to Troubleshoot - Refer to: How to Troubleshoot the Fuel and Emissions Systems(2.0L Engine) or How to Troubleshoot the Fuel and Emissions Systems(3.0L Engine) .
- The fuel system is designed to allow specified maximum vacuum and pressure conditions. Do not deviate from the vacuum and pressure tests as indicated in these procedures. Excessive pressure/vacuum would damage the EVAP components or cause eventual fuel tank failure.
Factory Service Tools
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.
