Why is the rum gone?
Join Date: May 2012
Location: United Kingdom
County: Greater Manchester
As a guess,
EGR Valve (as you have already figured)
If it has been stuck partially open for a while you would have had poor low down power (which you had become accustomed to), for some reason it decided to stick fully open which caused your limp mode EML and lack of power.
But now it's decided to stick closed, so you get the EML (which could go off by itself after a few ignition off/on cycles) but all the advantages of a blanked EGR.
If your near the Trafford Centre drop me a line, I have ODB reader and MES, I'll read the codes for you.
If it continues to drive well thats a bonus, but you might find it gets hit and miss depending on how the EGR feels day to day. Might be worth just blanking it off? (and either live with the EML have it mapped out or find a fixitsan dongle)
Having said that it might not be the EGR (but its my guess that it is)