Audi A4 (B6) 1.9TDI Limp mode after EGR delete?

[Sprinter2012]

Since I fitted my Darkside EGR delete pipe, my car sometimes goes into limp mode now. Normally only under high load at constant revs in a high gear. e.g. climbing a hill at 60 in 4th with the revs around 3000rpm.

A few things to note:
1. I blanked the EGR around 8 months before, and it ran beautifully with that configuration.
2. I then finally got the car remapped by Awesome GTI who also mapped out the EGR. Again, ran perfectly for months like that.

It was only months after that when I fitted the EGR delete pipe that I noticed this issue. As far as I can tell both vacuum pipes are properly blanked. And I used a high quality mikalor clamp to join the 90 degree elbow to the aluminium pipe, so the seal there should be fine too...any ideas?

 

[pauldazzle]

Sounds like it could be sticking turbo vanes causing overboost & then limp mode.
If it's been into limp there should be a fault code logged in the ECU.

 

[Mike.M]

As above or you have a boost leak somewhere

 

[Sprinter2012]

Well if it is that simple then I'll fix it tomorrow! All I'll have to do is remove the blanking plate as the pipe is already gone.

And I've even got a tin of Mr Muscle from when I cleaned the EGR valve after I removed it, perfect!