Tc and abs lights on?

i'm driving a 1999 vectra on a t reg first i had an engine light on so i replaced the lambda sensor and that solved that but now iv got my tc and my abs light on but only comes on after i've been driving it for about 1 hour plus it keeps stalling and the speedo stops working? it's been on a diognosis machine but won't connect then i've been told it's had another engine put in so can anyone please advise me wat it is or could be xxxxxxx

Anthony
April 2012