[Konstantinos]

First of all, sscanf doesn't work like that.

pawn Код:

new
    driftid;

    if( sscanf( params, "i", driftid ) ) return SendClientMessage(...);

But in your case, I suggest you to use isnull like you used, without sscanf.
Also,

pawn Код:

if( strcmp( params, "1", true ) == 0 )
{
    if(IsPlayerInAnyVehicle(playerid))
    {
        if(GetPlayerState(playerid) == PLAYER_STATE_DRIVER)
        {
            SetVehiclePos(GetPlayerVehicleID(playerid),-358.1943,1531.2909,75.1698);
            SetVehicleZAngle(GetPlayerVehicleID(playerid), 264.7289);
            SetCameraBehindPlayer(playerid);
        }
        else return SCM(playerid, -1, ""COL_RED"Error:"COL_GREY" You must be the driver of the vehicle.");
    }
    else
    {
        SetPlayerPos(playerid,-358.1943,1531.2909,75.1698);
        SetPlayerFacingAngle(playerid, 264.7289);
        SetCameraBehindPlayer(playerid);
    }
}
// Continue..