Hello, finally posting in correct bit. 1995 2.6 Cabriolet. 4 years off road, final suspension and brake work done. New cambelt, waterpump, etc etc. Passed on everything but CO2. Before retest changed the Cat, ran for 20 miles with Cataclean, half filled with premium fuel, ran it hot and high revs for 20 mils on way to centre but 0.57% reading on a 0.30% target for fast idle (no change from first test). Passed normal idle (just). People have mentioned full service, spark plugs etc but also O2 sensors. Do any of you gurus have any thoughts please?