Limp mode on the morning commmute

Driving in to work today and car is running normal. 20 miles into commute, turn the corner, up the hill and *poof* ...Emissions workshop and limp mode. '05 B5, 89k miles. Pulled the MAF connector off at lunch to get it to run better.

Just had the upper hose/elbow for the turbo circuit replaced about 2 months ago after it split..made for nice thick black smoke and no power. (sooted up the intake???)

Checked all the turbo hoses tonight and they are not split. Also changed fuel filter. Still in emissions workshop.

Last few months have been giving low to mid 30's on MPGs; tonight with the MAF off, it was up around 40 on same driving route. Not sure if its finally cooling off, if its a case of less go-pedal and less romping, or if something else is going on.

You need to retrieve the fault codes. Besides the obvious one for MAF that you now have, we need to know what else there is (if any) to properly diagnose.

P0299 (Turbo underboost) is the main code
also a code for MAF sensor being off (off to get it to run better).

possible diagnosis of a bad/sticking turbo, but not sure if that makes sense. still leaning towards a bad sensor.

Had that happen about 2 years ago and the VW dealer replaced the (G31) valve and checked some acutator rod.
At least that is what it says on the VW dealer Invoice / Receipt.
Maybe a guru can explain better.