Our beloved Audi 8l 1.8T S3 has become rather unwell since my wife has been running it on E10 due to economic factors. We have used Shell V-Power and it ran like a dream, but the fuel cost became prohibitive, so my wife, trying to budget sensibly and buy fuel more affordably for us as a family, started using E10 as we were advised the car should be fine on it. Any thing but, the fuel economy tanked, it became noisy and now we seem to have costly engine problems. With hindsight, this was most certainly a false economy. I have another cherished petrol fuelled car, and there's absolutely no way I'm running that on E10 after this horrendous experience. I've just reduced my use of that car.
