Yes, higher rpm uses more fuel
If it is malfunctioning it can affect fuel mileage.
All of the engine sensors can affect fuel mileage.
yes
No, a small hole in a silencer does not affect the fuel consumption.
Yes it will.
It can affect the cost, fuel guzzler tax.
3 - 7 MPG. Fuel mileage is determined by a number of things.. the engine, for one. The speed the vehicle is operating at, the gear ratio and RPMs being turned at those speeds, the stochiometric ration (fuel/air mixture), driver habits, etc.
How it rides, handles, fuel mileage and power are affected.
Yes, if the added length adds weight to the vehicle. The more the car weighs the less fuel mileage it will get.
It could make it better, but nost likely make it worse.
No. The charcoal canister does not have a noticeable affect on fuel economy.
Yes .. it does .. change it immediately.. it drinks fuel like crazy.. mileage goes down ...