4kq fuel pump relay question & O2 sensor reading

[CTDiesel at aol.com]

1. With 4kq fuel pumps isnt there suppose to be a momentary hummm. when you
turn the key before you engage the starter?  I think i had that up to about 6
months ago and now nothing?  If thats the case isnt it time for a new fuel
pump relay?  Are any german made relays ok or are there some to avoid.  Napa
has German relays but they arent Kracker.

2.  I know the settings on O2 sensor ranges (.2 to .7 fluctuating
continually) but I've noticed that you can turn the adjustment screw several
times either way, rich or lean, and the computer makes the adjustment fairly
quickly afterward.  So how are you suppose to know where to set the mixture.
The digital readout doesnt read constant high or constant low so you can make
the change the computer makes that change instead.  But that much change must
make the car run way rich or way lean.  Can someone help me out?

Thanks
DJ