[itsCody]

Detect if the engine is off then kill the timer.
Or detect if the vehicle is moving by using some speed script
if((speed) > 1) Fuel --;

Could try something like

PHP код:

public timer_fuel_lower()
{
    for(new i = 0; i < MAX_PLAYERS; i++)
    {
        new vid = GetPlayerVehicleID(i);
        new speed = GetPlayerSpeed(i, false)
        if(isrefuelling[i]) continue;
        
        if(fuel[vid] > 0)
        {
            if((speed) > 1) fuel[vid] --;
            if(fuel[vid] >= 1 && fuel[vid] <= 15 && GetPlayerState(i) == PLAYER_STATE_DRIVER)
            {
                SendClientMessage(i, -1, "Vehicle low on fuel");
            }
        }
        
        if(fuel[vid] <= 0)
        {
            fuel[vid] = 0;
            // Turn the engine off here.
        }
    }
    return 1;
}
GetPlayerSpeed(playerid, bool:kmh = false)
{
    new Float:Vx,Float:Vy,Float:Vz,Float:rtn;
    if(IsPlayerInAnyVehicle(playerid)) GetVehicleVelocity(GetPlayerVehicleID(playerid), Vx, Vy, Vz); else GetPlayerVelocity(playerid, Vx, Vy, Vz);
    rtn = floatsqroot(floatabs(floatpower(Vx + Vy + Vz, 2)));
    return kmh?floatround(rtn * 100 * 1.61):floatround(rtn * 100);
} 


If you get errors post them cause this is untested and yeah