I don't know if yours has leads on the front 3 plugs (early models) but mine has been transformed since I freed the flap on the VIS and changed the front leads and spark plugs. There was a factory bulletin about lead to plug cap connections deteriorating causing the spark to have to jump the gaps. The plugs on the front bank were eroded quite badly 2mm instead of 1mm
. I also fitted the
throttle/ fuel injector repair kit
My car has only done 50k but well worth the effort.