I have a 250 mile commute for some temporary work. Usually, I'm seeing 75-80 mpgs. I set the cruise at 60 and let PIMA work it's magic. However, yesterday on my drive back I was getting 60mpgs. That's a drastic difference in mpgs, with no change in driving styles or route. The only thing I can attribute to this incredible loss was the fact that I filled up gas before I left. I never by exxon gas, but had no choice this time because the tank was nearly empty. About 30 miles down the road, I was experiencing a huge loss of HP. On the flat with no wind the SGII was reading 45TPS in 5th gear just to keep up speed!!! It should read in the teens or low 20s. I checked tire pressure, all were at 56psi, checked under the car, nothing dangling or dragging. Any ideas? Could it be some bad gas? Has anyone ever experienced anything similar?