Question

What is code P0442?

P0442 code is defined as “Evaporative Emission Control System Leak Detected (Small Leak),” implying a minor leak in your car’s Evaporative Emission Control (EVAP) system.

The Evaporative Emission Control (EVAP) system is installed in a car in order to keep fuel vapors from escaping into the air. This is made possible by absorbing these vapors and storing them in charcoal pellets inside the charcoal canister installed within the car.

Two control valves help in this process. One is a Vent Control Valve, which controls the flow of vapors using the car’s powertrain control module (PCM). The PCM opens the vent control valve, which lets air into the charcoal canister, where it’s burned together with any remaining gas fumes before the air enters the engine. In addition, a purge volume control valve regulates the rate at which gas vapors escape from the charcoal canister and enter the engine’s air intake.

The vent control valve is open during normal engine operation. The purge volume control valve is active when the PCM is ready to burn off the accumulated fuel vapors. Overall, this helps the car to emit less.

The PCM performs a leak test to check that the evaporative emission control system is operational. During the leak test, the vent control valve and the purge valve are shut to seal the evaporative system. If the PCM finds a leak in the EVAP system, it sets the P0442 engine code.

What are the symptoms of code P0442?

The most common sign is the illuminated check engine light. These are some other symptoms you can observe when the PCM logs this code.

• Decrease in fuel economy
• Fuel odor near or inside the car
• Failed emissions test

What is the most common cause of the P0442 code?

These are some reasons why the code appears in your car.

• Defective or loose fuel cap
• EVAP system line leakage
• Charcoal canister leakage
• Damaged vent or purge valve
• Fuel tank leakage
• A small hole or crack in a fuel vapor hose or tube
• The fuel cap doesn’t satisfy the car manufacturer’s standards
• Defective FTP sensor
• Damaged or leaking charcoal canister

How to fix the P0442 code

These are some common steps to follow to fix the error code.

• Replace the fuel cap
• Repairing or changing defective hoses
• Replace purge or vent valves
• Clear the error code from the car’s PCM

Can I drive with a P0442 code?

Yes, ideally, you can drive with code as a minor leak in the evaporative emissions (EVAP) system won’t instantly impact your car’s safety or performance. However, you must fix the issue quickly. Driving with the code for a long period can cause decreased fuel economy, an increase in emissions, fuel odor, and a failed emissions test.

How much does it cost to fix P0442?

The P0442 engine code fix cost may range between $20 and $1,000 based on the underlying issue, car, and location. Fixes like replacing the gas cap will cost below $50, but the rate can be higher for issues like replacing the fuel tank or charcoal canister.