I take it this will be doing a lot of short trips/stop,start driving? I would have thought twice about buying anything with a particulate filter and generally avoid any French motor,you could try and give the motor a long run in low gears preferably without stopping to get the exhaust really hot and try and burn off excess debris from your exhaust,have seen these glowing red to try and get them cleaned out and actually melting tar which is why you should keep away from other motors,especially behind you.
cdc
February 2013