What Does P0456 Mean on Your 2020 Dodge Charger?
A P0456 code on your 2020 Dodge Charger reveals that the PCM has detected a very small leak—about 0.020 inches—in the evaporative emission control system. Your Charger uses Stellantis's (formerly FCA) NVLD (Natural Vacuum Leak Detection) technology to monitor the EVAP system's sealed integrity with remarkable sensitivity.
Whether your 2020 Charger packs the 3.6L Pentastar V6, the 5.7L HEMI V8, the 6.4L HEMI V8 (Scat Pack), or the supercharged 6.2L Hellcat, all variants share the same fundamental EVAP system architecture. P0456 is an emissions concern only—your Charger's legendary performance remains completely unaffected.
Common Causes: Investigating the Evidence
- Gas cap seal wear (30%) — Five years of use gradually degrades the rubber seal. The Charger's capless filler system (if equipped on certain trims) or traditional cap can both develop leak paths.
- NVLD sensor malfunction (22%) — Stellantis's Natural Vacuum Leak Detection sensor is the primary EVAP monitoring component. It can develop internal faults or cracks over time.
- EVAP line deterioration (18%) — Five years of heat cycling from the engine bay (especially on HEMI models generating significant underhood heat) and road vibration can crack or loosen vapor lines.
- Purge valve seepage (15%) — The purge solenoid can develop slight leak-through when commanded closed, particularly on high-heat HEMI applications.
- Charcoal canister damage (10%) — The canister's underbody location makes it vulnerable to road debris impacts over the years.
- Fuel tank or filler assembly seal (5%) — Tank seals and the filler neck grommet degrade with age.
Diagnostic Steps
- Gas cap check — If equipped with a traditional cap, replace it ($15–$30) and clear the code. For capless systems, inspect the filler door seal for debris or damage.
- Visual EVAP inspection — Check all accessible vapor lines, connections, and the charcoal canister for physical damage or loose fittings.
- Smoke test — The gold standard for finding a 0.020-inch leak. Low-pressure smoke fills the EVAP system, revealing the escape point.
- wiTech NVLD test — Stellantis's wiTech diagnostic tool reads NVLD sensor data in real time, confirming whether the sensor is functioning correctly.
- Purge valve testing — Verify the purge solenoid seals properly when commanded closed and opens cleanly when commanded open.
Repair Costs
- Gas cap: $15–$30 (DIY)
- NVLD sensor: $200–$400
- EVAP hose repair: $100–$250
- Purge valve: $150–$320
- Charcoal canister: $280–$550
Warranty and DIY Notes
Your 2020 Charger's 3-year/36,000-mile Stellantis basic warranty has expired, but the federal emissions warranty covers EVAP components for 8 years/80,000 miles through 2028. Check your mileage—you may still be covered. DIY feasibility is moderate; the gas cap is easy, but the NVLD sensor and smoke testing require more expertise.