Hi Folks,

2001 A3 engine AVU was juddering this morning and subsequently wouldn't start.

Turns out to be engine code P0404: EGR valve issue, which the AA recommend I replace asap.

Tapping the valve with a hammer did the trick for now.

Is this easy to replace myself?

It failed the MOT on emissions ~300 miles ago. Lambda sensor 2 was replaced.

Could the EGR have caused the MOT failure?

Or could the new sensor be causing the new problem?