[DJDhan]

At the top somewhere:

Code:

#define HOLDING(%0) \
	((newkeys & (%0)) == (%0))

Code:

OnPlayerKeyStateChange(playerid,newkeys,oldkeys)
{
  if(IsPlayerInAnyVehicle(playerid))
  {
      
    if (HOLDING( KEY_FIRE ))
    {
       do
        {
        new Float:x,Float:y,Float:z,vehid; vehid=GetPlayerVehicleID(playerid);
        GetVehicleVelocity(vehid,x,y,z); 
        SetVehicleVelocity(vehid,x+30,y+30,z+30);
        } while(x<200 && y<200 && z<200);
    }
  }
  return 1;
}