hi there im hoping someone can help me..ive got a hyundai matrix diesel 1.5 3 cylinder..recently the engine has started making a loud metallic knocking noise when revs reach around 2000 rpm.engine management light on when i accelerate the engine cuts out and i have to wait 3 or 4 mins before it will start again....i would be very grateful if anyone could help me ..many thanx ..cuckoo