[[NoV]LaZ]

Код:

native GetVehicleHealth(vehicleid, &Float: health);

In layman's terms, & (ampersand) before a variable means that the data is stored in that variable.

pawn Код:

new Float: health;
GetVehicleHealth(vehicleid, health);
if (health < 1000.0) 
{ 
    // do something
}

You might want to use TextDrawSetString for that. Destroying the textdraw many time a second isn't a good idea.