Re: pump fuel / running problems
Yes, especially engines with carburetors. The oil companies are throwing all kinds of end oils and chemicals into the fuels lately, so they don't have problems disposing of them, and, they formulate the fuels for use in EFI systems, which don't require the better quality to perform acceptably. Fuels injected as a very fine fog-like mist, under extremely high pressure, react very differently than fuels inducted by vacuum pull signal, in raindrop sized droplets. What would seem a tuning disaster to a carb'd engine, is not even a hiccup in an EFI engine.