P0456 on the Final 2023 Dodge Challenger
A P0456 code on your 2023 Dodge Challenger—the final model year of this iconic muscle car—indicates the PCM has found a very small leak (0.020-inch equivalent) in the EVAP system. While any check engine light is unwelcome, especially on a collectible final-year model, P0456 is a minor emissions issue fully covered by your warranty.
Your 2023 Challenger uses Stellantis's NVLD (Natural Vacuum Leak Detection) system, identical across all trims from the V6 SXT to the supercharged Hellcat and limited-edition Demon 170. The EVAP system operates independently of the drivetrain—your Challenger's legendary performance is unaffected.
Likely Causes
- Gas cap not fully seated (35%) — The simplest explanation. A cap that didn't get the final click won't seal properly.
- NVLD sensor sensitivity (20%) — The NVLD unit may read slightly off, or Stellantis may have a calibration update available.
- Software calibration (18%) — PCM updates can adjust EVAP monitor thresholds for the final model year.
- EVAP connection looseness (12%) — A factory or service-related connection that's not fully engaged.
- Purge valve irregularity (10%) — Marginal purge solenoid sealing during the EVAP monitor test.
- Filler assembly or tank seal (5%) — A seal that hasn't fully bedded in during early use.
What to Do
- Check the gas cap — Remove, inspect, reinstall firmly. Clear the code if possible.
- Dealer visit — With full warranty coverage, let the dealer diagnose and repair at no cost. They'll use wiTech and check for TSBs.
- Software update — The dealer applies any pending PCM calibrations.
- Physical repair if needed — Smoke test and component replacement, all under warranty.
Costs
- Under warranty: $0—covered through 2026 (basic) and 2031 (emissions)
- Gas cap (DIY): $15–$30
Warranty and Collectibility
Your 2023 Challenger carries the 3-year/36,000-mile basic warranty through 2026 and the federal emissions warranty for 8 years/80,000 miles through 2031. As the final year of the Challenger, these cars are increasingly collectible—keeping maintenance records of warranty repairs only enhances long-term value.