Having EGR issues all pipes and EGR valves been stripped cleaned and working correctly the only issue I can see in multiscan is the intake quantity sensor is reading lower than desired volume it follows the desired set point when driving on normal roads but as soon as you get on the duel carriageway or motorway or under hard acceleration it drifts massively away from the desired set point
Also I have a sensation of being pushed up the backside when it’s setting down after accelerating when van starts to coast this shows a spike above the desired set point from the air quantity sensor
This problem is pinging the PO401-61 EGR high pressure blockage code

Is it the MAP sensor or MAF sensor supplies this reading

Regards Paul

Things we have done so far are

New EGR valve
Stripped and cleaned all pipe work and EGR cooler
Removed inlet manifold and cleaned
Cleaned MAP sensor
Checked all pipe work for leaks including all vacuum pipes
Turbo waste gate moves freely
Turbo boost pressure valve changed with known working one

Not had chance to check electrical circuits yet auto electrician busy until next week.... only had chance to check actuators and all sensors in multiscan