I have some problems that concern me.The first one is i put 40 dollars of gas into the vehicle and 60 miles it was almost near the empty with the combination of black smoke when i'm at a stop light and pushing on the gas just enuff to do the speed limit.second my speed sensor is not working do to the speedohmeter needle does'nt move when the car does.I have code 42 which is the speed sensor and 51 which is the air conditioner switch ,neutral start switch signal.I have no idea what is making the extreme gas consumption and the black smoke.can a faulty speed sensor cause the extravagant consumption of gas? S.O.S