Seemed like I lost my turbo this morning on my b5 tdi. Had very little power but after i drove about 6miles it all seemed ok. I thought a boost pipe had come off but it can't be that cos its working again now. Any ideas what it might be?

maybe the bearing in the turbo is getting a bit stiff.

how many miles has it got in it ?

maf or boost solenoid could be on their way out?

Is there a carbon sensor in the exhaust mark? my sisters alfa diesel done what your discribing and it was this sensor that was fucked.

pretty sure they dont have sensors in the exhaust

sounds like i went into limp mode for alittle bit to me, try putting it on vagcom if you can, could be that youve got a small bost leak some were and only leaks when cold but once its warmed up closes the gap

air mass meters play up aswell if happens again try disconnecting and driving. it will go into a default setting and should feel quick again. but boost soleniod sounds more at fault.