[Konstantinos]

If you keep this in OnGameModeInit/OnFilterScriptInit:

pawn Код:

SetTimer("DerbySys",1000,1);

then change to:

pawn Код:

forward DerbySys();
public DerbySys()
{
    for (new playerid; playerid != MAX_PLAYERS; ++playerid)
    {
        if (!IsPlayerConnected(playerid) || !IsPlayerInRangeOfPoint(playerid, 500, -1364,1004.5,1220)) continue;
        if (!IsPlayerInAnyVehicle(playerid))
        {
            GetDerbyCar(playerid);
            continue;
        }
        if (IsPlayerInVehicle(playerid,RandDerbyCar[playerid]))
        {
            new Float:Vhealth;
            GetVehicleHealth(RandDerbyCar[playerid],Vhealth);
            if (Vhealth <= 250)
            {
                DestroyVehicle(RandDerbyCar[playerid]);
                SendClientMessage(playerid,0xFFFFFFFF,"Vehicle was destroyed. New vehicle created.");
            }
        }
    }
}

Else you'd have to set the timer when a player joins the derby:

pawn Код:

SetTimerEx("DerbySys", 1000, true, "i", playerid);

and use it as you have it but keep in mind to store the timer ID in an array and when a player leaves derby to destroy the timer.