lloydworks

Hi all I am new to this forum, I have a 2007 IS220d with 84500. Have had it over a year and its been driving like a dream. The last few days as its colder, when starting up and its in neutral the revs drop from 1200 to almost the point where it feels like its going to cut out then back up again. Also if I engage first gear or second when its cold and i go to drive it feels like its going to stall. As soon as the car is warmed up its fine again. I had a guy check diagnostics as there are no warning lights and he revved the motor and says it looks like there is a restriction in flow and the EGR valve and naifold will need cleaning. From your experience do you think this is the case? thanks