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 gas fumes from escaping. This code means there's a small leak letting some of those fumes out.
The EVAP system prevents fuel vapors from escaping into the atmosphere. A P0442 code indicates a small leak has been detected in this system.
The P0442 code is triggered when the vehicle's Engine Control Module (ECM) detects a small leak in the EVAP system. This system is designed to capture and store fuel vapors from the fuel tank and prevent them from escaping into the atmosphere. The ECM monitors the system's pressure and can detect leaks as small as 0.020 inches.
• Check Engine Light is on
• Slight fuel odor
• Possible decrease in fuel efficiency
• Loose or damaged gas cap
• Cracked or disconnected EVAP hoses
• Faulty purge valve
• Defective vent valve
• Leaking charcoal canister
EVAP: Evaporative Emission Control System
ECM: Engine Control Module
• Check the gas cap for tightness and damage
• Inspect EVAP hoses for cracks or disconnections
• Perform a smoke test to identify leaks
• Test the purge and vent valves for proper operation
• Tighten or replace the gas cap
• Replace damaged EVAP hoses
• Replace faulty purge or vent valves
• Repair or replace the charcoal canister
• OBD-II scanner
• Smoke machine
• Multimeter
• Vacuum gauge
$100 - $300
Moderate
• Toyota Camry
• Ford F-150
• Honda Accord
• Regularly check and tighten the gas cap
• Inspect EVAP system components during routine maintenance
• Replace worn or damaged hoses promptly
Emission Control
• Check the gas cap first; it's often the simplest fix.
• If the Check Engine Light remains on, seek professional diagnosis.
EVAP system components may be covered under emissions warranty for up to 8 years or 80,000 miles.
The P0442 code has been a common issue since the introduction of OBD-II systems in 1996, as manufacturers have tightened emissions standards.
Low – This code does not affect immediate drivability but should be addressed to prevent emissions issues.
Ignoring this code can lead to increased emissions, which may be illegal in some areas and could result in a failed emissions test.
• Vehicle at operating temperature
• Fuel tank between 1/4 and 3/4 full
The EVAP system components are typically located near the fuel tank and engine bay.
Q: Can I drive with a P0442 code?
A: Yes, but it's best to fix it soon to avoid emissions issues.
Q: Will a P0442 code cause my car to fail an emissions test?
A: Yes, a P0442 code can cause your vehicle to fail an emissions test.
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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.