[Konstantinos]

Delete stock SetCarPos;

pawn Код:

stock SetCarPos(playerid, Float:Vx, Float:Vy, Float:Vz, Float:Va, Float:Px, Float:Py, Float:Pz, Float:Pa, interior)
{
    TogglePlayerControllable(playerid, 1);
    if(GetPlayerState(playerid) == PLAYER_STATE_DRIVER)
    {
        SetVehiclePos(GetPlayerVehicleID(playerid),Vx,Vy,Vz);
        SetVehicleZAngle(GetPlayerVehicleID(playerid),Va);
        LinkVehicleToInterior(GetPlayerVehicleID(playerid),interior);
    }
    else
    {
        SetPlayerPos(playerid,Px,Py,Pz);
        SetPlayerFacingAngle(playerid,Pa);
    }
    SetCameraBehindPlayer(playerid);
    SetPlayerInterior(playerid, interior);
    return 1;
}

And replace the SetCarPos(carid) to SetCarPos(playerid, Float:Vx, Float:Vy, Float:Vz, Float:Va, Float:Px, Float:Py, Float:Pz, Float:Pa, interior)

Since I don't know what exactly do you want this function does.