NOT KNOWN FACTS ABOUT PEUGEOT ADBLUE DELETE

Given that past diagnostics / code clearing drove three miles and light again on / engine turned off straight away ad blue filler cap taken out and attempted to blow/suck by cap to determine if ventilated. Cap is NOT ventilated. still left cap off and tissue in filler neck for eighty miles/no lights arrived on.No, not all diesel automobiles use AdB