Was it full till it clicks ?? I recon It must just be your dial freaking out I know Scoobys are in now way frugal but you should return an average of atleast 25 mpg with some spirited driving I return 33ish and even more on a run and I've got 650cc injectors and a bigger turbo. although in stock trim a quarter of a tank in 40 odd miles is defiantly doable if doing very spirited driving because at WOT it will drink a lot and I mean a hideous amount, and cold starts with high idol will use a lot trying to warm the cats. My recommendation would be, if it does it again go strait back to the pet station and brim it till it clicks again, then you know for sure how much fuel you have used.
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