Hi again! Thanks for them Peter.. the links worked so thats progress! I dont know why the others didnt - I'll have another try later. Thanks again for your trouble there. I took the cat off today after removing the sensor and testing revs strength which seemed very much improved... On removal of the cat I shook it and it rattles well! A look inside proved the cat was definatly duff for it had come away and was rolling around inside the box. So, a bit previous to list a 'fix' as I cant get a new one till Monday but Im hopeful and will let you know then. Thanks very much again for the inputs thus far. Mike