I’m rather familiar with erratic fuel gauge problems in the ‘95 940s, seemingly in particular the turbos. The fuel pickup assembly has a longer barrel and the fuel level sender is a slightly different design from earlier 700/900s with the smaller tank. The float rides between two sensor coil rods. The metal contacts on the float are a butterfly shape and the wings can wear out leaving a jagged edge that catches on the coils and at times may not floating properly thus giving incorrect readings. The resistance wire on the coils is progressively wound. Initially it tends to catch at the top and gives inconsistent readings as the fuel level drops, either freeing itself by its own weight or driving over a bump. After a while the problems start happening at lower fuel levels.

I’ve long suspected this wear is accelrated or made worse on cars that live on rough roads, such as gravel, as I was told the first owner of my turbo did and as confirmed by the shotgun of paint nicks on the front edge of the hood.

The pickup assemblies are expensive and NLA n the parts chain, so you need to find a good used one from a lower mileage '95 940. I'd have to check if the '94 turbos also got the larger tank, but I recall not. I did a crude repair rebuilding the contacts by clipping tabs on the stubs of the wings that has now lasted over 15 years, but over the past 6 months it’s started acting up again. One of these days the fuel pump will go and I'll break open the sender barrel to see what's happened. Cracking open the barrels is not trivial and not for the faint of heart as you risk breaking it plus you can cause permanent damage as well when handling the coil rods.

For whatever reason this has yet to happen on my other ‘95 940 that’s also Bosch single pump with even higher mileage, just crossed 400K km the other day.

As for longevity. I have had to replace the pump once on that NA at about 300K km, but the turbo is still on the original pump at 375K km. I was hesitant to put in the smaller aftermarket Waller/Helbro pump that is significantly cheaper than the Bosch original, but at 100K km it seems fine. Pumps are also known to last longer if you drive around mostly with a full tank rather than empty due to both cooling being immersed in fuel and also the greater lift for the pump..

I vaguely recall any difference between the NA in-tank pump and the turbo pump is the working pressure spec.
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Dave -still with 940's, prev 740/240/140/120 You'd think I'd have learned by now