i bought my car and it has never worked the speedometer, i changed it to another one and it seems to be doing the same. Changed the speed sensors and still does the same. a friend told me that the new speedometer that i got is messed up as well but i dont really think that it is.

plus the battery light comes up and more energy is sent to the car but when the light is not on it looses energy.... why could this happend ? shouldnt it be the other way around :>

 

What you really need is a new altenator.

 

so because of the alternator is why is doing both things ?