Egr excessive flow detected

[Britj]

Hi

A few weeks ago i set off to work it was quite foggy and my 2011 2.0cdti insignia and p0402 fault code kept coming up
i must of reset it about 15 times before i got to work

On the drive home it faulted another couple of times

The next few days no faults at all until it was foggy again and faulted again a few more times same fault code

Ive cleaned the map sensor egr and the pipe at the side which had loads of muck in i also read on here to clean
maf sensor is that the air flow sensor connecter to the air filter and how would you clean it

Any way after all that and its is still doing the fault intermittently

Is there anything else i should be looking at

[lizzard-t]

Make sure the EGR is actually working.
Excessive flow either denotes that the EGR is not functioning or there is a air leak.
Which you would either have to search for get it smoke tested .