[V8] fuel level sender

[urq]

IME Fuel Level Senders are never difficult to R&R ... but many times there's
nothing wrong with them.  

With the V8 there are several diagnostics you can do to verify it is indeed
the tank sender ... I suspect similar techniques will be available on the
newer cars.  Unfortunately, you may not be able to tell if some of the other
readings are based on a faulty signal generated elsewhere.  

On the V8 you can activate the instrument cluster diagnostics, which set the
fuel gauge to a particular level, see if your 100 isn't the same.  

When I bought my first 5-speed V8Q and was driving it back to California
from Colorado I found that there were some questionable readings.
Eventually I realized that the "miles to empty" reading on the trip computer
was different from the fuel gauge.  If you see one reads good and the other
does not then it ain't the sending unit.  

If you have the service manual for the car you should find additional
diagnostics.  Usually you can connect a fixed value resistor in place of the
sending unit and check the reading on the gauge.  You can get resistors at
Radio Shack.  

Good luck!
Steve Buchholz

-----Original Message-----

Thanks, Kent.  It really doesn't look like rocket science.  Now to find a
sending unit without going through the Audi Stealer.

Roger

-----Original Message-----

Roger Woodbury wrote:
> My wife's 100CS Avant Quattro has a severely malfunctioning fuel gauge.
My
> wrench suggests that it the sending unit, and he and I both assume that
this
> is a floating kind of thing located in the fuel tank.

I haven't replaced one, but the Family Album shows it to be just what you'd
think -- a float on an arm going to the sender.

Roger -- see the images the list will strip.

-- 
Kent McLean