1998 Buick Park Avenue Owner's Manual - Page 282

When you put the cap back on, turn it to the right until you hear a clicking sound. Make sureyou fully install the cap. The diagnostic system can determine if the fuel cap has been left off or improperly installed. This would allow fuel to evaporate into the atmosphere. See "Malhnctiom Indicator a p " in the Index. L NOTICE: If you needa new cap,be sum to get the right type. Your dealer can get onefor you. If YQU get the wrong type, it may not $it properly. This may cause youp:malfunction indicator lamp to light and YOU^ fuel tank and emissions system may be damaged. see "Malfunction hdicatos Earnp'' in the Index.