[William1122]

Code:

stock StopRefueling(playerid)
{
	GivePlayerCash(playerid, -100);
  	SendFormattedMessage(playerid, COLOR_WHITE,"Your vehicle's tank has been refilled for $100.");

Code:

forward ReFill(playerid);
public ReFill(playerid)
{
	if(!IsAtFuelStation(playerid) || !IsPlayerInAnyVehicle(playerid) || VehicleFuel[GetPlayerVehicleID(playerid)] >= 100.0 || GetPlayerCash(playerid) < 1)
	{
		StopRefueling(playerid);
	}
	else
	{
	    new engine,lights,alarm,doors,bonnet,boot,objective;
    	GetVehicleParamsEx(GetPlayerVehicleID(playerid),engine,lights,alarm,doors,bonnet,boot,objective);
		if(engine == VEHICLE_PARAMS_ON) return StopRefueling(playerid);
		VehicleFuel[GetPlayerVehicleID(playerid)] += 1.0; RefuelingVehiclePrice[playerid] += 30;
		if(VehicleFuel[GetPlayerVehicleID(playerid)] >= 100.0) VehicleFuel[GetPlayerVehicleID(playerid)] = 100.0;
	}
	return true;
}

I didn't exactly know wich one of the two so I posted these two hope this is what you mean