View Single Post
  #9  
Old 30th July 2018, 12:39 PM
ainarssems ainarssems is offline
Senior Member
 
Join Date: Aug 2010
Location: Rushden, Northants
Posts: 3,802
Default

I am not sure these restrictor plates do much or anything at all on modern engines which determine how much EGR is open based on measured airflow. If something is blocking EGR flow and metered airflow is too high ECU will just open EGR valve more, if the air flow or EGR duty cycle is out of tolerance sit will throw error code. Have a look at measuring blocks in VCDS for specified and actual airflow and EGR duty cycle. If the specified and actual airflow ar close together you have not made much difference on amount of EGR entering engine, if the EGR duty cycle % is high it means ECU is opening EGR valve more to meet the specifications. It would have been great for comparison if you had a log before and after fitting plate.

Restrictor plates were working for older cars like 1.9TDI where EGR was only mapped in ECU as duty cycle and not as specified airflow on newer cars. Basically on old cars ECU just looked at the map and choose EGR duty cycle depending on rpm and injected fuel quantity and did not care about airflow, on newer cars it looks up required airflow depending on rpm and injected quantity and then adjusts EGR valve duty cycle to meet specified airflow value.

You can turn off or reduce EGR by remapping ECU and on some ECUs you can adjust it through adaptation with VCDS as well.
__________________
Currently 8less
2011 Q7 S Line 3.0TDI, 2016 Tesla Model S 90D

8 history:
2006 A8 Sport 4.2TDI quattro SOLD,
1997 S8, reached end of life with gearbox failure
Reply With Quote