its easy to know what it is but theres not much you can do yourself. its either your speedometer cable or your speedometer sensor. only place you can get either piece is from honda. im not positive if they will just sell you either part without doing labor themselfs but for you to know which one it is you pretty much need them to detect what part is broken. Both items are kinda pricy and it sucks ass. they will also lecture you that if you dont have them fix your speedometer you can go to jail for mileage fraud since when they fix it they go and turn back however many miles you "driven" its all **** though. but both parts are ontop of your tranny so check it out and make sure theres no chaffing and that the sensor is even connected. good luck