Just one wee thing......these engines rely on over injection of diesel to help clean out the DPF.
Do observe the oil level closely in case it rises!
John
Do observe the oil level closely in case it rises!
John

Ok, why did you use him ?The reason I am asking here is because the mechanic who scanned and cleared is clue less himself and whoever I have further asked is also and are just guessing on potential causes. I am checking in this forum to understand if someone here has had the same issue and what were the necessary steps or remedial measures taken so that I can then get the next mechanic to look at it.

post 15Mate I am here to get answer to my query/issue rather than argue on something that is not necessary, if you are not aware of the issue then fine. Every mechanic might not have an answer to all the issues and this is one of them. I have also checked with couple other mechanics on this issue and they are not aware either on the real reason for it. It could be a EGR, head gasket or dpf or waterpump issue is what they are pointing to. As mentioned earlier I am checking in this group if anyone has either come across or heard of this issue who can then guide me in the right direction rather than me loosing 1000's of bucks trying different mechanics, hope you understand now.
I am astounded none of your mechanics have been able to narrow it down by carrying out some or all of these tests unless of course there is no fault to find. Take the car for a run locally. If the head gasket has gone it will show up soon enough.

At this point with all the information available all anybody can do remotely is guess.Many mechanics are simply parts swappers, with limited diagnostic skills.