On Mon, 20 Feb 1995, Larry MacPhee wrote:

shortened:

> when we're getting low on gas, but the replacement gas guage behaves as badly 
> (or perhaps as well as) the first.
> 
> Symptoms:  Fill the tank and the guage reads full.  Drive a bit and the guage 
> dips to 1/2 full, back up to 3/4 and after driving a bit more down to 1/4 and 
> sometimes towards empty.
> 

I experience the same problem with my '80 Vanagon Camper: the guage reads 
full after refill, drops to half within 50-70 miles, jumps around a bit 
(especially when vertical or horizontal forces are applied) and 
disappears to the left after approx. 120 miles....

I think - with reference to some earlier discussion on this list - that 
is related to

(1) the weird shape of the gas tank;
(2) a malfunctioning (misadjusted) sender unit (located in the tank).

Possible solutions:

(1) Drop the tank and adjust/replace the sender;
(2) Ignore the problem and rely on known fuel consumption and 
    driven milage (I get between 15 - only downtown - and 24 - pure 
    highway - mpg with a camper conversion/pop top and 2.0l FI w/ 4gear MT)
(3) Install one of these fancy computers that measure miles driven, actual 
    fuel flow etc etc etc, and ignore everything else that you ever 
    looked at. 

Marcus
'80 Vanagon Camper, 2.0l FI

****************************************************************
Marcus G. Doherr, Dr. med. vet.
Graduate Group Epidemiology
VM: Medicine & Epidemiology
UC Davis, CA 95616; USA
Phone (916) 752 6409 (Office 1136 MS1A)
      (916) 752 6409 (Graduate Group Office)
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