u/thatonegirl2014

My check engine light recently came on, took it to the dealership and they said it was bad fuel, recommended doing a tank of 91 and sticking to Top Tier gas. Have been putting exclusively chevron, was fine with 91, however when I tried chevron 87 the check engine light came back on towards the last quarter of a tank, put 91 back in and it turned off. Anyone else experience something like this? I don’t believe it’s bad fuel if the check engine light is coming on with Chevron 87.