Yeah that bad gas is a pain. I had a case where bad gas lead to detonation which cracked a plug insulator.The EFI engine seemed to idle ok, but wouldn't take a load. I isolated the cylinder swapped in a new plug and away it went. A couple of weeks went by and the car showed up again. This time a different plug. I swapped in 4 new ones this time and told him to find a new gas station. I never saw it again.
