can the use of magnets help in automobile navigation??

Answer 1

Yes as well as many other uses for magnets.
I use magnetic drive pumps in my garden pond.
No oil to worry about leaking out and killing the fish, just change the impellers when needed.
Magnets and GMR Materials
Solid State Physics
http://www.ill.fr/dif/3D-crystals/magnets.html
Our View on Saving Fuel with Magnets
http://www.kjmagnetics.com/fuelmagnet.asp