4kq fuel pump relay question & O2 sensor reading

Tigran Varosyan tigran at tigran.com
Tue Dec 3 18:07:27 EST 2002

Don't know anything about O2 stuff for this car but the fuel system I now
know. The fuel pump will stay on for about 2 sec after you turn OFF the car
to pressurize the system for the next start. It does not turn on until you
start cranking.


-----Original Message-----
From: quattro-admin at audifans.com [mailto:quattro-admin at audifans.com]On
Behalf Of CTDiesel at aol.com
Sent: Tuesday, December 03, 2002 5:18 PM
To: quattro at audifans.com
Subject: 4kq fuel pump relay question & O2 sensor reading

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
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
the change the computer makes that change instead.  But that much change
make the car run way rich or way lean.  Can someone help me out?


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