P0455 on a Toyota Tacoma
P0455 means evaporative Emission System Leak Detected (Large Leak). On the Tacoma, a few causes come up far more than others.
What P0455 usually means on a Tacoma
P0455 on a Tacoma is a large EVAP leak — the system can't hold vapor pressure. The cheapest and most common cause is a loose or worn fuel cap, so that's always the first check. Trucks also expose the EVAP hardware — charcoal canister, vent valve, and hoses — to more dirt, water, and road salt than a car, so those components fail here too. There's no drivability effect; it just lights the dash and blocks emissions readiness.
Most common causes on the Tacoma
- Loose or failed gas cap
A cap that won't click or has a hardened seal causes many Tacoma P0455s and is a trivial fix.
- Charcoal canister leak
The underbody canister on a truck is exposed to grime and water and can crack or lose its seal.
- Vent valve stuck open
A vent solenoid that won't seal, sometimes fouled by dirt, prevents the system from holding pressure.
- Cracked or damaged EVAP hoses
Underbody lines on a truck take road debris and salt and split with age.
What P0455 costs to fix on a Tacoma
Begin with a genuine Toyota gas cap, which costs only a few dollars. If the leak is in the canister or vent valve, those parts are moderate but mounted underbody where a truck collects grime, so allow for cleanup and access labor. A smoke test finds the leak so you fix it once.
Year, engine and mileage change the answer. Start a case and Redline weighs these causes against what your car shows, then names the check that would settle it.
Other codes on the Toyota Tacoma
Related symptoms
Toyota Tacoma problems & recalls by year
Based on widely reported patterns for this model; individual causes vary by year, engine and history. Generic P0455 behavior is covered on the main P0455 page. Confirm with a scan tool before buying parts.
P0455 on your Tacoma?
Every problem becomes a Case. Tell Redline what your Tacoma is doing: it shows what the evidence supports, what’s still missing, and what to check next, before you approve a repair.
“Inner pad ~1 mm. Outer pad 3 mm.”
Next: check the slide pins move freely before buying parts.