I cannot speak to a Thor 4.0/4.6 but I would say your 93 D1 had major issues. I had a 3.9 D1 and I would get around 14l/100km cruising on the highway, 17 around town and 22 offroad. I had the car for 12 years and recorded fuel consumption for the entire time I had it - of course in specific circumstances it would give better or worse but the average is sort of what it averaged out.
Now my current 101 with a 3.5 gives 22 on the highway and I can do better if I go slower so your 22 average indicates that you had major issues somewhere.
Oh - very early D1 3.5s had flapper injection, the 3.9 D1s had 14CUX and the 4.0 D2s had Thor - no Gems either. Gems was fitted to earlier P38 4.0/4.6 engines and later these came with the Thor system.
Garry
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