I've discovered a strange noise coming from my engine.
It sounds somewhat diesel-like - low-freq knocking, very similar to a single valve clearance not properly adjusted.
Not very loud, heard only with music off and hvac on 1st-2nd speed.
But is is very annoying, for a new (4000 kms so far) Japanese engine...

I guess I should diagnose it at the dealer.
The problem is dealer could charge me over $500 for valves adjustment.
I've found in my Warranty and Maintenance book that adjustments in first 20000 are covered.

Anyone has such experience?