Belts, pump, tensioner and idler are out of service time of 6yr by some margin.
To check inlet manifold is simple:
Remove power vis (the one on the top) it's a simple electrical plug and four screws and off it comes.
Look into the hole it came out of and you will see a brown arm with a slot in it, this arm should move side to side and be free but firm in movement.
Any up and down movement other than flexing of the arm is wear. For the butterflies to be making such a racket the arm would have to be detached from the butterflies to allow them to be swinging and rattling about, it would be very evident on this test if this was the case. Do not start the engine whilst carrying out this check.
Costs nothing to check for this fault
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