ELLO AGAIN!!! a while ago my engine management light came on and i took the car to audi to diagnose it.... they said nothing was wrong and it had come up "by accident". I definateley noticed a power loss between 3-4k rpm but i thought i might be just imagining it. Then i started noticing other changes like getting from 80mph to 100mph was a real drag and took much longer to get to than before. Also the 100-120mph was a struggle and it would be near enough impossible to get up to 130mph. This kind of speed was all tested on a rented airstrip by the way so yeah in the past the car would go from 120-130 in around 10seconds with a full car and full boot. Now it will hardly get to 120. My final blow was last night, i went to see my mate with a standard 1.8 A4 and he totally wiped me out and he wasnt even putting his foot down!!! Audi said there was nothing wrong with the engine at all and there were no fault codes coming up (as i take it to my mechanic every 3 or 4 weeks) I have read on some of the threads that there is a "limp mode" that the ecu can engage. could this be the problem? or maybe a faulty turbo? my mechanic recons the waste gate is getting blocked so i bought a K03s replacement. it has not been fitted yet but it will be soon enough before the end of nov so i will let everyone know how that gets on. I thought it may be the air/pressure sensor. I took the car to my mechanic about a week after taking it to audi and he said he got a fault code saying the cat is faulty so maybe this could have something to do with it?? For now i would really appreciate any help. even if it is just an idea. If any one else has had similar problems and solved it, please let me know. THANKS!!!