2003 Chevrolet Impala Owner's Manual - Page 261

1 If you get fuel on yourself and then sometnmg ignites it, you could be badly burned. Fuel can spray out on you if you open the fuel cap too quickly. This spray can happenif your tank is nearly full, and is more likely in hotweather. Open the fuel cap slowly and wait for any "hiss" noise to stop. Then unscrew the cap all the way. Be careful not to spill fuel. Clean fuel from painted surfaces as soon as possible. See Cleaning the Outside of Your Vehicle on page 5-86. When filling the tank do not overfill by squeezing in much more fuel after the pump shuts off. When you put the fuel cap back on, turn it to the right (clockwise) until you hear a clicking sound. Make sure you fully install the cap. The diagnostic system can determine if the fuel cap has beenleft off or improperly installed. This would allow fuel to evaporate into the atmosphere. See Malfunction lndicator Lamp on page 3-36. While refueling, let the fuel cap hang by the tether below the fuel opening. To remove the fuel cap, turn it slowly to the left (counterclockwise).