I noted that whenever I used E10 fuel in my 2009 Commodore Omega wagon on a recent trip up the coast to Cairns and back towing a 4.5-metre pop-top van the consumption shown on the trip computer went up by approx 5-10 per cent, from around 16.0-16.5 L/100 km on 95-octane fuel to 17.5-18.5 L/100 km on E10. The benefits seem questionable?
The increase in consumption you report is certainly higher than would be expected, but that could be because you were towing. Try it again in normal day-to-day driving and see what you get. The expected increase in consumption is about three per cent and that should be offset by the lower price of E10.
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