I've got an even easier test. Next time you park it, stick a wadded up paper towel or piece of gum in the carb vent. Then wait a few days, come back, DON'T FORGET TO REMOVE THE GUM, and crank it over. If it starts, it was an evaporation problem. If it just cranks, it must've leaked out somewhere.

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'86 Bronco, 460, E4OD; '85 Ranger, 350hp 289, T5, 12.9@110.5
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