Hello I have an 95 Acura Legend coupe, my speedometer needle sometimes goes crazy and the overdrive D flashes

you need a speed sensor,go to almost any auto salvage yard and buy a used one for about $50...the part is the same for all legends from 1991 to 1995 and a tl3.2 from 96 thru 98,after you're done,disconnect the battery for 20 min to re-boot the cars computer