Strange fuel indication problem w/'95 940 - Help!

I have my '95 940 w/165K miles in a friend's shop. He is trying to figure
out a problem with fuel indication.

I recently had the fuel qty. sending unit replaced with new one after the
old one died. Now, it indicates empty, complete with the orange warning
light even though it has about four to five gallons left in the tank. The
old sending unit never used to do this until I had about one gallon left in
the tank which I figured was about normal. I don't have the owner's manual
handy at the moment since it is with the car in the shop, but I imagine it
mentions how much fuel should be left when the warning light comes on. Does
anyone know?

Also, though probably not related, the car "runs out of gas" and won't start
while it is parked in my driveway, which is inclined downwards, even though
it has four or five gallons in the tank. My mechanic friend points out that
the pump is located at the very end (I can't remember if it is the forward
or the rear end of the tank), but it still can't scavenge the remaining fuel
in the sump unless the car is more level. My remedy is to add a gallon of
gas so that the car starts, even though there is plenty left (4 or 5 gal).
It never used to do this until I had the sending unit replaced.

Anyone have an idea what is going on here?


Thanks,
Bob

 

I'd say you have the wrong sender, it doesn't reach the bottom of the
tank. The pump (and fuel pickup) is mounted on the end of the sender
unit.

--
Mike F.
Thornhill (near Toronto), Ont.

Replace tt with t (twice!) and remove parentheses to email me directly.
(But I check the newsgroup more often than this email address.)

 

Thanks Mike.

Your suggestion makes sense, and we thought about that possibility as
well. However, the mechanic assures me that it is the correct part (I
ordered it myself), and its appearance exactly matches the original one
we took out. He said there is only one way it can fit in and it is in
all the way, so I'm pretty sure that is not the problem. It is
possible that the sender is partially defective where it seems to work,
but is not calibrated correctly.

Bob

 

bob...my 93 940t has aprox 3 gallons when the
warning light "kicks off"......

 

Thanks. That's good data to have. Maybe there's a wide range on the
fuel quantity remaining when the warning LED comes on.

That's not the way my system *used* to work, but I can live with it
once I get used to it. What I can't live with is the car not starting
(out of gas) when parked on a hill and there's four or five gallons
left in the tank.


Bob

 

From the manual for the 95 940 on the US Volvo Site:

"The total fuel tank capacity is approx. 19.8 US gals (75 liters). When the
warning light comes on, there are approximately 1.6 US gals. (6 liters) of
fuel remaining in the tank. See "Refueling" for further information. "

and in "Refueling":

"The fuel tank is designed to hold approximately 19.8 US gals (75 liters)
with sufficient volume left over to accommodate possible expansion of the
fuel in hot weather. Be aware that the "usable" tank capacity will be
somewhat less than the 19.8 US gallons (75 liters) maximum. When the fuel
level is low, such factors as ambient temperature, the fuel's "vapor
pressure" characteristics, and terrain can affect the fuel pumps' ability to
supply the engine with an adequate supply of fuel. Therefore, it is
advisable to refuel as soon as possible when the needle nears the red zone,
or when the fuel warning light comes on. "

Hope this helps,

Rob