I'm also getting 1 - 3 hard pings on medium acceleration on hot days, then power drops, I'm assuming from the ECU backing off the timing and/or throttle. This can't be healthy, right? Also, I'm using 91 octane. Please let me know if the dealer has acknowledged this one.Has anyone experience this issue? I have a 2015.5 S60 T5, when accelerating, I get this ticking/clicking noise for about a second or so. And it feels like its losing power. Usually occurs between 3k to 4K rpm. I feel like I don't get that quick torch. Any idea?