ford fiesta starting problem

[airslack]

I have a 1994 fiesta freestyle 2 with passive anti theft system. when i turn the key the engine turns over but won't fire, however when i disconnect the multi switch opposite the key side of the barrel i can turn the steering lock off with the key and insert a screwdriver into the multi switch to start the engine which works fine. any ideas?

[Bramble43]

Sounds like the transponder in the key or the reciever is going faulty, with columb plastics removed, slide the black plastic ring with rectangle box which is on the steering lock nearer the key , maybe even as far as near the top of key and try it, if it wont start then it could just be the multi switch at fault, if you are in or near Bristol you could try Harris on Ford in keynsham for help.