Afternoon all!
Our 2013 4D56 has got issues with the EGR valve. P0401 insufficient flow detected. Took the valve off & the valve can be opened easy enough & it closes without any assistance.
Is there a way to test these valves or is it a case of throw a new one on & see what happens?
Many thanks all!👍

You can watch the valve opening and closing using an OBD scanner that has Live Data
The valve is controlled by a Leccy motor, pretty sure you can just buy the motor and swap it.,
Chris Valentine sells a box that keeps the EGR valve closed, but yours needs to be 100% working to fit one.

Thanks for that Nick,
Plugged `er in & got into live data. put the graph up & got flat lines. No apparent movement shown so went back to numeric display & no alteration to figures. Guessing there's a wire broken somewhere....Are there common areas in the loom where this happens or keep cutting off the wrapping?
Bit of a puzzler..
Anyway, these are the codes i got off it.
P0401 egr flow insufficient
U1102 ASTC ecu time out
D110H/53520 undocumented code
U1101 a/t ecu time out.
Any thoughts on this? Old bus is a bit to nice to fix with petrol & matches....

I know the EGR valve is supposed to test it's self on start up
Was there any movement if you reved the truck?
Other option is to test the plug with a multi meter to check for a feed.
If you have a power probe take the EGR valve off and see if you can power probe it open / closed