No power

Alright people. Been a member of the forum since buying a mk1 octavia vrs about 2 years ago but only used it as a source of info a couple of times as don't really have much time to spend on internet. Now I'm in need of help! Changed clutch on my car and it had new speed sensor too, problem is now it idles ok but acceleration is poor. When in gear it seems to go into limp mode but no lights on dash. Vcds scan shows no errors. Can anyone shed light on this or point me in the right direction?