Idle Stabilizer Valve, how tight?

[Claus Vegener]

Got the code 2231 and pulled the valve.
It works with 12 V on it, but I am able to
blow by mouth either way through it with
only a little resistence.
Shall I try the sealed adjustmentbolt ?

Symtoms: just before the code lights up the timing is retarded and slightly fat running starts. After 10 min. of no-idle driving
engine runs OK again and shut off error light.
Idle is too high 1200 rpm

Claus