Hi all it's been awhile since I've been here! Well, my recent problem is the Check Engine light has gone on. It went on for about an 1 hour or so during some errands then it went out and didn't come back on until about a week later. I noticed that it would come on after I just filled up my tank, lately I've been using Mid Grade Octane89 since gas prices are nuts, but before that I was using Premium Octane91+. So I guess my question is, that using cheaper gas is having a problem with my O2 sensor or something? I haven't got the codes pulled yet but I will later today at Autozone. So any suggestions or comments would be appreciated, thanks in advance my Volvo friends!

 

Sounds like an EVAP system problem to me. Those usually come and go depending on fuel tank capacities. Example, if you notice light comes on only after less thenhalf a tank or maybe a quarter of a tank, then after refueling, say you fill it up to 3/4 tank and if goes out. Or any noticable pattern similar to that, I would recommend getting codes pulled and reposting if you cannot correct problem. GL (could also check condition of fuel cap o ring)