Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
Your car has a system that keeps gasoline fumes from escaping into the air. This code means there's a big hole or opening in that system, like if you left the gas cap off.
The EVAP (Evaporative Emission Control) system prevents fuel vapors from escaping into the atmosphere. A large leak indicates a significant failure in the system's ability to contain these vapors.
The P0455 code is triggered when the powertrain control module (PCM) detects a large leak in the EVAP system. This could be due to a loose or missing gas cap, a cracked or disconnected hose, or a faulty component within the system that allows fuel vapors to escape.
• Check Engine Light is on
• Noticeable fuel odor
• Possible decrease in fuel efficiency
• Loose or missing gas cap
• Cracked or disconnected EVAP hose
• Faulty EVAP canister or vent valve
EVAP: Evaporative Emission Control System
PCM: Powertrain Control Module
• Check gas cap for tightness and condition
• Inspect EVAP hoses for cracks or disconnections
• Perform a smoke test to locate leaks in the EVAP system
• Tighten or replace the gas cap
• Repair or replace damaged EVAP hoses
• Replace faulty EVAP canister or vent valve
• OBD-II scanner
• Smoke machine
• Basic hand tools
$50 to $200
Moderate
• Toyota Camry
• Ford F-150
• Honda Accord
• Ensure gas cap is properly tightened after refueling
• Regularly inspect EVAP hoses for wear
• Replace gas cap periodically
Emission Control Issue
• Check and tighten your gas cap first
• Visit a mechanic if the light remains on
EVAP system components may be covered under emissions warranty, typically up to 8 years or 80,000 miles.
The P0455 code has been common since the introduction of OBD-II systems in 1996, as emissions standards have become stricter.
Moderate – While not immediately critical, it can affect emissions and fuel efficiency.
Driving with an EVAP leak can lead to increased emissions and may fail emissions testing.
• Vehicle at operating temperature
• Fuel level between 15% and 85%
The EVAP system components are typically located near the fuel tank and engine bay.
Q: Can I drive with a P0455 code?
A: Yes, but it's best to fix it soon to avoid emissions issues.
Q: Will a loose gas cap cause a P0455 code?
A: Yes, a loose gas cap is a common cause of this code.
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Fitment Required · Vehicle-fitment part
Relevant for some EVAP leak codes where the fuel cap or sealing surface is part of the problem.
Some EVAP leak faults involve the fuel cap or its sealing surface.
Fuel caps vary by vehicle and should be matched to the exact application.
View options on Amazon
Fitment Required · Vehicle-fitment part
Relevant when EVAP diagnosis points toward purge-flow or purge-control faults.
EVAP diagnosis often includes purge-flow and valve-control faults.
Confirm the failed valve and exact fitment before buying parts.
View options on AmazonThese parts may be related to this fault category, but a code by itself does not confirm exact fitment or guarantee that replacing a part will solve the problem.