1.9 tdi sport Quattro juddering!

[John Crossley]

Just bought an Audi A3 1.9tdi Quattro, everything fine apart from when I accelerate usually in 5th/6th. It rumbles/judders very loudly. If I take my foot off the pedal it runs fine, no judder. I'm not very farmiliar with cars so I need help. Looked online and found it could be flywheel, cv boot/joints, or injectors. Could someone please reply and let me know what to do. Thanks,
John.

[Rob69]

If you got it from a dealer take it back - could be engine mount, I think there is a dog bone mount on them, or sounds like flywheel away to me which is probably why it was sold on.

[John Crossley]

I text the guy I bought it off (private sale) said he is going to email me later with what he thinks it could be, he says he's certain it's not the flywheel. What about cv joints, is there a way I can go outside right now and check without lifting the car?