P0455 on a 2013 Ram 1500

P0455 means the EVAP system failed a leak check badly enough that the computer sees a large leak or no pressure/vacuum change.

Not your vehicle? See general P0455 info.

Most common causes on the 2013 Ram 1500

Ranked from 1,254 NHTSA owner complaints filed for this vehicle.

Sort by:

1
Corroded fuel tank strap/frame mount dropping the tank and cracking/disconnecting EVAP lines or the filler neck seal
High severity
The dominant pattern in this batch: the front tank-strap frame mount rusts through (same failure recalled on 2009-2012 Ram 1500s, not extended to 2013), letting the tank hang and stress attached EVAP hoses/filler-neck seal enough to open a large leak.
Reported in 20 NHTSA complaints
Parts:fuel tank strap fuel tank mounting bracket
2
Faulty gas cap or cap seal
Medium severity
Owner reported a recurring 'check fuel cap' warning with the check engine light and no other cause found.
Reported in 1 NHTSA complaint
Parts:gas cap
3
Sticking fuel filler neck / ORVR valve failing to reseal
Medium severity
Owner described the fuel nozzle repeatedly sticking in the filler tube, consistent with a binding filler-neck valve that can also fail to seal, opening a large-leak path.
Reported in 1 NHTSA complaint
Parts:fuel filler neck
4
Blocked or malfunctioning EVAP vent path (fuel pump clicking off while filling)
Medium severity
Owner reported the fuel pump repeatedly shutting off during a 30-40 minute fill, indicating an EVAP vent-path problem that can also present as a leak once the restriction clears or the valve fails open.
Reported in 1 NHTSA complaint
Parts:EVAP vent valve EVAP canister
5
Split or disconnected large-diameter EVAP hose
Medium severity
A hose popped off a fitting or split open is a classic large-leak source.
Common cause
Parts:EVAP hose/line
6
EVAP canister vent valve stuck open
Medium severity
A vent valve that fails to seal prevents the system from holding pressure/vacuum during the self-test, registering as a large leak.
Common cause
Parts:vent valve
7
Cracked charcoal canister housing
Medium severity
A cracked canister housing is a large enough opening to register as a big leak.
Common cause
Parts:charcoal canister

Part links go to Amazon search results for this vehicle. As an Amazon Associate, WrenchConnect earns from qualifying purchases — always confirm fitment for your exact trim and engine before ordering.

These causes are aggregated from NHTSA owner complaints and general repair knowledge — this is not a diagnosis. P0455 on your car still needs shop confirmation before any repair.

Common symptoms

Check engine light
Fuel smell
Usually no performance issue
Failed emissions readiness

What to check before replacing parts

Check the gas cap first

Look for: A loose, missing, or cross-threaded cap is by far the most common cause of a large EVAP leak code — if it doesn't click to full tightness or the seal is cracked, that's very likely the whole fault.

Inspect visible EVAP hoses

Look for: A large leak is often obvious: a hose disconnected at a fitting, split open, or chewed through (rodent damage is common) rather than a hairline crack.

Command the purge and vent valves with a scan tool

Look for: A valve that doesn't respond at all when commanded open/closed, or stays open when it should seal, prevents the system from holding pressure/vacuum and reads as a large leak.

Smoke-test the system

Look for: With a large leak, expect an obvious plume of smoke or a clearly audible hiss at the fault location — it should be easy to spot compared to a small-leak diagnosis.

Inspect the canister and filler neck

Look for: A cracked charcoal canister housing or a corroded/rusted-through filler neck (common on older vehicles) can leak enough to prevent the system from ever holding vacuum.

Rather have a pro handle it? Find a vetted local mechanic.

Matching symptoms

Check Engine Light