At owner's own risk of attempting cleaning
Steps below are only for illustration for my own servicing.
For parts, get from Honda stockist.
This is the VTEC spool valve
Unless engine is sludged and the user does engage VTEC at the required rpm (approx 5000 to 6500 rpm) will the ECU divert the solenoid valve to divert oil into the VTEC cams.
You can say that in normal D mode, rarely does the VTEC gets engaged in everyday driving.
There is one bolt on the body holding the electrical connector cable.
The bigger bolt is removed.
Sludge is removed using a carb spray.
The soldnoid is held by two bolts at the top.
The lifters are sprayed and o rings renewed (using my own o rings).
These o rings are just seals and will not see any rubbing.
The insides are cleaned.
Ready for re-assembly.
Oil is applied onto the 3 o rings before assembly.
These are the oil ports on the engine block near the cams.