hi there ive just joined the names jay. can any one help just bought an alfa 156 2.0 drove fine for about 20 mile then i noticed a knocking noise on acceleration but when i stopped acelerating it went at first i thought it was the heat shield rattling as it sounded like that but i got about another 10 mile then started to hear the same noise continueously also affecting acceleration eventually i had to stop as was very loud sounding quite similar to a neumatic drill, it starts ok still makes noise and wont tick over if i drive it acceleration is vertually non existant will slowly climb in speed. Strange thing is i can just about hear the normal sound of the engine through the racket and its running pretty even. I checked the cam belt as i thought this might of stripped some teeth and slipped but its in good condition with no sign of damage so i am lost. hope that some one can help. and save me stripping the whole thing down.