Transmission

My car dont shift into third gear its a automatic. my brothers freind drove the car yesterday and he said that it needs a vacuum sensor or some sensor replace. thats why it wont let it shift into third it shifts fine from 1st to 2nd he said theres a sensor that just needs to be replaced. thats what he said is he right and if so how much would it cost to replace.

there's a whole procedure in itself to pull automatic transmission trouble codes... try searching thru nicoclub.com or www.240sx.org for more info...