On fuel economy affect a variety of factors: it features an engine and transmission, mass and loading the car, the aerodynamics of the body, rolling resistance, timely maintenance, condition roads and, finally, the manner of driving. When driving in urban environments with relatively low-speed rolling resistance is more important for fuel economy rather than aerodynamic drag. Bandwidth Rolling resistance depends mainly on the design of the tire carcass. On the characteristics of radial-ply tires are far superior tire with bias ply: they not only reduce the rolling resistance by about 50%, but also improve the grip on wet or snowy roads, besides they are more durable. Cold start the car engine friction and in the power transfer is very large, significantly worsens the fuel economy compared with those typical for start-up fully warmed-up car. In a new or newly renovated car losses due to friction in the engine can be large enough. As the fitting parts friction is gradually reduced.
In good technical condition and proper adjustment of the car is the key to the normal fuel consumption. So, for example, Improper installation of ignition timing improves fuel consumption by 15%! As for maintenance, there is, first and foremost, you must promptly change the air filter. As you know, with a lack of air for cooking fuel-air mixture is consumed much more gasoline. Also need to regularly check your tire pressure – under-inflation adversely affects the fuel consumption (to get adequate performance, it should be done on cold tires).