How to Fix & Reset the Check Fuel Cap Light on a Honda Accord

• Turn off your car and open the fuel door. Screw the fuel cap on tightly and start your vehicle to make the light turn off.
• Check the purge valve connected to the engine to see if it’s stuck open, and replace it with a new part if it’s damaged.
• Inspect the vent valve connected to the gas tank on your Honda Accord, and replace it with a new one if it’s clogged or broken.

Causes for “Check Fuel Cap” Message

Loose or broken fuel cap The Check Fuel Cap error on a Honda Accord usually appears when your vehicle’s EVAP system senses a leak near the fuel cap. It could mean the cap wasn’t properly screwed on, the rubber gasket is worn, or there’s damage preventing a tight seal. Other symptoms: strong gas smell, reduced fuel efficiency Diagnosis: Open the fuel door on your Honda Accord and unscrew the fuel cap. Inspect the cap for damage, and check the round rubber gasket for cracks or tears.

Faulty purge valve The purge valve (or solenoid) is a cylindrical piece next to your vehicle's engine intake and prevents fuel fumes from escaping into the air when your engine is off. When the purge valve fails, it may get stuck open and trigger a Check Fuel Cap warning. Other symptoms: poor engine performance, rough idling, reduced fuel efficiency, and hard starting after adding fuel Diagnosis: Connect a vacuum pump to the intake on the purge valve and squeeze the handle. If the vacuum pressure goes down after pumping, then the purge valve is leaking.

Stuck vent valve The vent valve is a small cylindrical piece on the side of your vehicle’s fuel tank, and it brings fresh air into the EVAP system while your engine is running. If the vent valve gets stuck open, your Honda may detect a leak and trigger the Check Fuel Cap message. Other symptoms: lit Check Engine light, strong fuel smell, gas pump clicks off when filling up Diagnosis: Disconnect the vent valve from your gas tank and connect the intake to a vacuum pump. If the pressure slowly drops after you squeeze the handle, then the vent valve has a leak.

Repairing a Check Fuel Cap Light

Tighten the fuel cap. Turn off your vehicle and open the fuel door on your Honda Accord. Check that the fuel cap is tight by wiggling it around. Then, unscrew the fuel cap completely and inspect the threadings for damage. Put the fuel cap back on and turn it clockwise until you hear it click and restart your vehicle. After tightening your fuel cap, it may take a few drives for the warning message to turn off. If you still see the message after 2 days, then there may be another issue. If you notice any dirt or dust built up on the fuel cap or where it connects to the gas tank, wipe it off with a clean lint-free cloth. The dirt or dust may have been preventing a tight seal. If your fuel cap is damaged or missing, then get a replacement cap. Typically, they only cost $10–15 USD, and you can install the gas cap on your own.

Change the purge valve if it’s defective. Locate the cylindrical purge valve on the side of your engine near the fuel intake. Disconnect the electric connector and the hoses from the old valve, and unscrew the bolts to remove it. Install a replacement purge valve in its place and reconnect the hoses and wires. Purge valves typically cost $15–30 USD. You may be able to clean the purge valve with mass air flow cleaner instead of replacing the part.

Replace the vent valve if it’s broken. Locate the vent valve underneath your vehicle connected to the side of the gas tank. Unplug the electrical connector and pry out the vent valve with a screwdriver. Slide the replacement vent valve into the port and screw it back on tightly. Reconnect the cord to finish your repair. Vent valves typically cost $20–50 USD.

Take your vehicle to a mechanic if the light remains on. Typically, it takes a couple of days or drives for the EVAP system to reset. If the Check Fuel Cap message turns off within 1–2 days, then you’ve solved the issue. If it stays on, take your vehicle to a mechanic to check for other leaks or issues.

FAQ

Can I drive with a “Check Fuel Cap” light on? While you may burn through fuel a bit faster, you can still safely drive your Honda Accord. The EVAP system won’t damage your engine or release harmful fumes in your car.

Can I drive without a fuel cap? It’s okay to drive without a fuel cap for the short term, but it will burn more fuel and cause warning lights to appear on your dashboard. If you need to have your vehicle tested for emissions, you’ll also need a working gas cap.