What we found
Across the 2018–2020 Jeep Wrangler — the first three model years of the current fourth generation — Jeep issued 29 manufacturer communications referencing diagnostic code P0456.
What P0456 means
P0456 is defined in the licensed DTC reference as “EVAP System Leak Detected (very small leak).” It’s part of the evaporative-emissions monitoring system, which checks the fuel tank and vapor lines for leaks too small to smell or see — a common trigger is something as minor as a loose or worn gas cap, though it can also point to a cracked vapor line or a faulty purge valve.
Which model years are covered
The bulletins concentrate in the Wrangler’s first three model years under its current generation (2018–2026 per the generation reference CarFaultIQ holds) — consistent with a code that often gets addressed through a running production or design change, which would reduce how often it shows up in later model years.
What this doesn’t establish
A manufacturer communication is dealer service guidance, not a safety recall, and it doesn’t mean a given vehicle has this condition. NHTSA complaint records separately hold 3,154 owner reports across all components for these years, not linked to this code, and cannot be turned into a failure rate.
For owners and buyers
P0456 is one of the lower-stakes codes CarFaultIQ tracks — it flags an emissions-system leak, not a drivability or safety concern, and the first thing worth checking on any vehicle throwing it is simply whether the gas cap is seated and undamaged. If a fresh gas cap doesn’t clear the code on a 2018–2020 Wrangler, the bulletin volume here suggests Jeep’s dealer network has a well-established diagnostic path for it.