Ok, so my car has what may appear to be a blocked cat (cant be 100% sure though) so what i plan to do is cut the cats off and put 2 simple bits of pipe (one size bigger than the cat pipe) in there place... i will fix these with 4 exhuast U clamps... If my problems are cured i will then buy 2 new (or low mileage) used cats and sleeve and weld them in place... Does this seem like a) a sensible plan before blowing money on cats b) a viable and fairly straightforward exercise... Dont worry about the SES light... i thik someone before me has had tat done, i had cylnder shut off and it didnt even come on!