JTD - clanking /knocking from top left of the engine
Over the past few days I have noticed a metallic knocking noise from the top left (cambelt side) of the engine.
It's not there when you first start up but after a few seconds it starts and varies with engine revs. It's loud enough to hear in the car when you're driving and regular.
First thought was an injector but I think it's further back than that. (I stuck a bottle of injector cleaner through it just in case)
I have also tried the 30 seconds at 3,000rpm 15 seconds at idle hydraulic lifter recharge procedure but no luck there either.
Performance is fine and normal, but I am slightly worried it could be something more sinister.
What else could it be? Fuel pump? I am really not sure where to start looking!
Thank you in advance!