Well after sitting listening to the exhaust I thought I recognise the sound it's making, after spending most of my youth polluting the atmosphere with 2 strokes it's pretty obvious now, it's running rich, this may explain my thermostat issue i have or thought I had. Sometimes when clearing the misfire codes it does sometimes have lambda codes, so as I'm changing the cat I'm also changing the lambda as a matter of course I'm hoping this will clear the problem. Checked the coil pack with the multimeter , all OK. I have even swapped the plugs, my god I have never fitted so many new parts in such a short time before, but then it doesn't get much spent on it so I had it coming. Parts arrived so far_ cat and spring compressor, yes I know they will come out without them but I will be doing this solo so any aides are a must. Just hope there is room to get them on the springs, after looking at the spring on the drivers side I'm ashamed I have allowed it to get that bad, last time I was under there they didn't seem that bad.