I am aware of the small relay behind the temp a gas gauges and that it controles both. However my question is Could it work for one and not the other?
My temp gauge works fine but my gas gauge will only read 1/4 tank after I fill up and then reads empty around 1/2 tank. So I have resorted to using my triptometer rather than the gauge. If it is not the relay thinger-mer-jigger what else could it be?
Thanks,
Wayne

If it were both acting funky, the voltage regulator would be
suspect, but if it is only one it is likely the sending unit,
the gauge, the wires, the nuts that hold the gauge in place,
or rocks in your gas tank.

I put a GT gauge cluster in my 164 and one of the 3 connectors
is a little loose and when it gets super hot out it can work
itself pretty loose and the temp gauge doesn't register anything
sane. If I just push it back into place the gauge works fine
for another 6 to 8 months.

I'd fill the tank and look at the resistance of the sending
unit then run the car for a while and look at the resistance again.
I'd also try grounding the wire on the sending unit to see if
the gauge swings to full (don't leave it like this or you may
screw up the gauge).

The volvo shop manual is likely the best place to look for a real
procedure for fixing this.
chris

It could be your gas gauge sender.
Check your green Volvo manual.
--
George Downs, The "original" Walrus3, Bartlesville, Oklahoma

I have seen the Green manuals and everyone here talks about them but where can I get a hold of one?

Thanks for the tips on the gas gauge I'll give them a try.

Wayne

I got one at a Volvo dealer in Panama in 1972 and another on ebay a couple
years ago. They show up from time to time on ebay.
I think that there is a literature section on VCNA's website. You may
be able to order one there. Be sure and specify the year as they are
single-year specific manuals.
(Both of mine are 1972 but they are broad enough that they cover most of
the problems in my 69 164 and later B20 engines, not to mention most of
my 1973 145.)
--
George Downs, The "original" Walrus3, Bartlesville, Oklahoma

And what is the exact title of this book?
Thanks again

PS I finally took some pic of my car with my ditigal camera and I was wondering how to add them to messages on this board when I need to?