[Haydz]

I would suggest using OnPlayerStateChange for using the timer, and you will need a seperate FuelTimerLower for each player( so don't cancel otherplayers timers)

pawn Код:

new FuelTimerLower[MAX_PLAYERS];
public OnPlayerStateChange(playerid, newstate,oldstate)
{
        if(newstate == PLAYER_STATE_DRIVER)
        {
              FuelTimerLower[playerid] = SetTimerEx("timer_fuel_lower",50000,true,"i",playerid);  
        }
        if(oldstate == PLAYER_STATE_DRIVER)
        {
              KillTimer(FuelTimerLower[playerid]);
        }
}

Then that would start/kill the timer for each different player. also, if you want it so it lowers the carfuel of the car you're in you will need to show us your 'timer_fuel_lower' function