[JuanStone]

PHP код:

PlayerTextDrawSetString(playerid, SpeedoText0,"Vehicle: %s~n~Speed: %i KPH"); 


This will display an incorrect text, you must make format above, the text you entered there must already be formatted.

PHP код:

ShowSpeed(playerid)
{
    new string[45];
    PlayerTextDrawShow(playerid, Speedo[playerid]);
    format(string, sizeof(string), "Vehicle: %s~n~Speed: %i KPH", {Float,_}..);
    PlayerTextDrawSetString(playerid, speedoText0[playerid], string);
} 


And add "[playerid]" and check that the variables have the correct tag.

PHP код:

new Text:var[MAX_PLAYERS];