My 82 yr old Dad has a D40 that started to blow a lot of white smoke then went in to limp mode. His mechanic replaced some injector pipes and a filter?, improved a little for a short while, problem came back with car in limp mode,then mechanic replaced the exhaust system, problem still there, now mechanic says computer needs re mapping. I called in to see mechanic today, he said the re mapping is to clear the EGR which is blocked, i was under the impression the EGR could be cleaned manually at the manifold. I think mech has been clutching at straws all the way along, either taking dad for a ride or not really knowing what to target. Does anyone think the re mapping is the next step? thx for any comments. Tom