Only if your defroster uses the A/C, otherwise heater will not effect gas mileage.
The heater uses the waste heat from coolant used to cool the engine, so has no extra load on the engine. The heat was going to waste anyway. You are just diverting it into the car instead of outside.
When a car runs, it produces heat as a wasted product. This heat is then used to heat up air and blow it at you. This heat will be created even when the heater is off, so using the heater should not lower gas mileage.
Simply put, the higher the mileage the less the value.
It can affect the cost, fuel guzzler tax.
My car has SUPER great mileage! It has the best mileage ever!
Provided the heater is of a low wattage it should not affect normal running of the car
The more mileage on a car the more wear and tear on the engine and transmission witch in turn can cause it to have problems.
Yes, if the added length adds weight to the vehicle. The more the car weighs the less fuel mileage it will get.
No it will not. It will either be leaking or become clogged which will make the heater not produce any heat. it has nothing to do with fuel mileage.
No
Cars don't get better gas or mileage.
How it rides, handles, fuel mileage and power are affected.
I disagree. I was having issues with my heater taking a long time to heat up. I had to have my battery replaced and my heater functioned normally after that.