Hi guys iv just brought an 03 plate st170 and wen driving its lovely but if I ty an put me foot down it won't go past 4000k iv have it plugged in to diagnostics and it sed cat is blocked/ nackerd I just wanted a second opinion before I spent a lot iv money buying 1 it's had a ful service with all filters and plugs and coil pack back in December the owner told me and I have receipts for this Just wounderd wat pple thort of this as its rrli annoying not being able to use all the power I no is there lol thanx in advance Chris