The exhaust seems fine, as for when it smokes it seems to be after the cars been running a while. For example I drove a couple of miles tuesday turned it off to go to tesco, home (about 1 mile) then about 40 mins later back out to get my girls. On arrival at the childminders it smoked so bad....the most I've ever seen to be honest. Today I did almost the same journeys , it smoked on initail start up but then it was fine however after I'd collected my girls it started puffing idling in traffic.Tonight when I was listening for the pumpI started it and the heater didnt fire at all. ? Thanks, Alex