Hi
i have an 1998 audi a4 avant 1.9 tdi 110hp afn.
since i bought the car it has always had a bit of a shudder under load in 3rd,4th and 5th then when it reaches around 2-3k rpm and then some times the boost kicks in with a little puff of smoke.
but the shudder wont clear unless floor it.
further more it over boosts when the engine is not upto full temp causeing it to go into limp home mode,
this some time happens when warm aswell please can you help as i dont wanna fork out for a n75 or a turbo as im sure your aware there fairly pricey.

any help would be great

cheers
colin