Do you know the feeling when you're about ready to flip over to reserve, you know the sound of the exhaust going in & out of tune (not backfiring). Well that started happening to me last night on the way into work, then this morning on the way home it got even worse. I didn't put seafoam in for a couple of tanks (ran out) so I'm off to get some and see what happens. The tach was jumping like crazy too. Seemed like it did it a lot at 3-5K but if I got on it hard it seemed pretty smooth. I was pretty low on gas so I filled up (took 2.9 gallons) so we'll see where this takes me.