Got Shell 93 Octane and now barely idles 1973 Dart 340

TRWRacing said

Fuel filter looked good unobstructed and I was able to blow threw it. The gas had a slight yellow tint to it.

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OK, good on the filter. The pickup sock in the tank could be plugged as well as the trash filters in the carb inlets if it has them. The obstruction in the tank maybe a splitter in the lower end of the tube. Try a smaller hose and twist it around some.

If the yellow gas was a piss yellow tint, then I'd agree on the 'going skunky'. Other yellow tints may be OK. If going bad, it would also have a distinct acrid odor to it beyond the normal gas smell.

BTW we run Shell 93 all the time in my son's 340.... runs great, and better than the local ethanol free fuels. It might be formulated a bit differently in Chitown in the summer (read here: Why Gas Is So Expensive During the Summer (And Especially in Chicago)) But I doubt that is the problem in this case; the change in running characteristics in the car were too great, unless it is was water or trash in the fuel.