Banging noise on M20

[Guest]

On my mates 320i, its making a banking noise, like 2 metal parts hitting against eachother, this is only when the car is revved abit (over 2-3k revs), the noise is most defo coming from under the rocker cover, the car has done 166k miles and needs a service, should we bother trying to fix it or just drop a 2.5 in? we want to fix it for the meantime whist he saves up for a new engine, but i thought the engine was gone at first but i think it maybe something simple, please help 6 cylinder boys!

[andyp]

it could be anything mate its hard to say without seeing it, but it could be the ends knocking or a rocker shaft or cam problem, it really is hard to say, poss even the water pump ,

[E30Adam]

I'd say whip off the rocker cover and see if there are any visible problems and go from there, could be you've got a snapped rocker!