After putting back NEW MAF .
JetForceHello dear people ,
lets sumarize my 10-20 posts :
I have audi A6 CDYA 176kw ( equal to CCWA A5) ...
I got error P0401 .
Replaced MAF , no luck
Replaced electronic part off EGR system , no luck
Cleaned intake manifold , cleaned small pipe on intake that comes from EGR ( you have pictures in previous posts ) , It was dirty but still error
Replaced EGR solenoid , no luck ...
Finaly i took EGR cooler and cleaned it ( it took all day to get off ,clean it ( with some ARF cleaner for grill and kitchen stuff ...Better than any "egr cleaner spray" ) ...
After that NO ERROR .
If anyone get same error , here is path i used to get rid off this . Thanks a lot guys for suggestion and helping about this ...
JetForceIt is really heavy job . My mechanic need 2-3 hours to get it and the same to bring back . There is no 2 egr cooler. In this engine . Below is Oil cooler and oil separator valve ( i also changed that , but it does not have any relation to P0401...
You have electric part of EGR
View attachment 177846
And you have cooler
View attachment 177847
I marked you vaccum part . It should work open and close flap inside . If it cant move it is 99% problem of P0401.
I heard in AUDI CENTER that sometimes that flap broke ( melted ) .
To get cooler you need 1 stuff to do
Remove oil filter complete with case
or to move little turbo and wigling cooler to get it off. It is realy heavy job. I reccomend mechanic to do .