Understanding P0456 on Your 2022 Dodge Hornet
A P0456 code on your 2022 Dodge Hornet means the PCM has detected a very small leak—approximately 0.020 inches—in the evaporative emission control system. The Hornet, Dodge's compact crossover sharing its platform with the Alfa Romeo Tonale, uses Stellantis's EVAP monitoring system to verify fuel vapor system integrity.
Your Hornet may be equipped with the 2.0L turbocharged four-cylinder (GT model) producing 268 hp, and the EVAP system is designed to capture and recirculate all fuel vapors. Even the smallest breach triggers this sensitive monitor.
Common Causes
- Gas cap seal issue (35%) — The most common trigger across all vehicles. A cap that's not fully tightened or has a slightly worn seal allows enough vapor escape to set the code.
- EVAP system connection looseness (20%) — As a newer platform, the Hornet's EVAP connections can occasionally have a fitting that's not 100% engaged.
- Purge valve irregularity (18%) — The purge solenoid manages vapor flow from the charcoal canister to the engine. A marginal seal can trigger P0456.
- Software calibration sensitivity (15%) — Stellantis may release PCM calibration updates that adjust EVAP monitor thresholds for the Hornet platform.
- Charcoal canister or vent valve issue (7%) — Less common on newer vehicles but possible if a component is slightly out of spec.
- Fuel filler assembly seal (5%) — The filler assembly seal may need time to fully bed in.
Diagnostic Steps
- Gas cap check — Remove, inspect the seal, reinstall with a firm click. Clear the code and monitor.
- Dealer visit recommended — The Hornet should be under warranty. The dealer uses wiTech diagnostics and checks for applicable TSBs.
- Software update — The dealer applies any pending PCM calibrations.
- Smoke test if needed — Pinpoints the physical leak location.
- Component replacement under warranty — Any faulty part replaced at no cost.
Repair Costs
- Under warranty: $0
- Gas cap (DIY): $15–$30
- Purge valve (out of warranty): $150–$320
- EVAP hose repair (out of warranty): $100–$230
Warranty Coverage
Your 2022 Dodge Hornet is covered under Stellantis's 3-year/36,000-mile basic warranty through 2025—check your mileage. The federal emissions warranty extends EVAP coverage to 8 years/80,000 miles through 2030. Contact your dealer to verify eligibility.