Date:         Sat, 29 Jul 2006 09:13:15 -0500
Reply-To:     Larry Alofs <lalofs@RCN.COM>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         Larry Alofs <lalofs@RCN.COM>
Subject:      Fuel gauge sending unit resistance
Content-Type: text/plain; charset=us-ascii; format=flowed

I don't know if it will help for those involved with the current fuel
gauge thread, but it seems like this data should be in the archives; I
could not find it in my Bentley.

I took the gas tank out of my "91 GL recently to replace the grommets
and for future reference measured the resistance of the level sensor.

With the empty tank upside down so that the float was in the "full"
position, the sender measured a reliable 35 ohms.

With it right side up, the "empty" position, the minimum consistent
resistance was 450 ohms.  This value was sometimes higher if I moved the
tank or tapped on it.  I assume that this means that the slider is not
always making good contact in that region because of wear.  Maybe this
has something to do with the gauge's erratic behavior when it gets down
to about a quarter tank.

If a person is trying to troubleshoot without direct access to the
connector at the tank, keep in mind that one of the wires leads to a
ground connection.  The Bentley is rather vague about its location.

Larry A.