I understand that:

 

EGR Duty Cycle 100% = EGR closed, no exhaust gasses recycled. 

EGR Duty Cycle 0% = EGR open with some exhaust gas being recycled.

 

Also that all sources I can find say that the EGR valve will be fully when idling and when accelerating with WOT.

 

The bit I don't get is why does this not translate into a 100% EGR Duty Cycle (monitoring Group 003 on VCDS).

 

On my car it is 95.5%, looking at other folk's logs on the Web this does not seem unusual. I can find very few references to a measured EGR Duty Cycle of 100%.

 

Anyone know what's going on?

 

Thanks

 

 

I guess you left out "shut" --  from memory it opens at idle every 2 minutes,     don't know if this applies here but with pneumatics it is standard to signal from say -10 to + 110    my numbers may be wrong but you get the drift   I'm sure a pneumatics expert will be  along soon :sun:

I guess you left out "shut" --  from memory it opens at idle every 2 minutes,     don't know if this applies here but with pneumatics it is standard to signal from say -10 to + 110    my numbers may be wrong but you get the drift   I'm sure a pneumatics expert will be  along soon :sun:

Thanks

 

Yes, meant to say 'Also that all sources I can find say that the EGR valve will be fully closed when idling and when accelerating with WOT.' - too late to edit correction into original post now though.