swathdiver
Full Access Member
Fuel prices generally speaking are falling in our area but as is often the case I do not always get to the least expensive station. Anyhow, for Christmas Eve, we drove about 180 miles averaging just over 39 mph and could barely get 12.1 mpg. Oil level is fine, tires equal and running about 52 psi once warmed up. LTFTs at highway speeds are 0% and at 40 mph are usually 3%. Alcohol content was 73%. At that ratio she should have delivered over 14 mpg on the highway and up to 15.2 @ 70 mph. Never happened.
Tonight we had a six hour run and the usual stations were not open. Topped off on the highway rest stop with E85 @ 78% alcohol content and barely averaged 13.5 mpg @ 71 mph. Fired up the Tech-2 on the return leg and could not find anything amiss. She should have seen just over 14. Cats were in the 1300s, downstream O2 sensors steady, upstream moving great but only into the 700s. Occasional torque management knock retard, about every 30-45 seconds, timing was usually 37 degrees. Load was about 100 foot pounds and 55-60% if I remember right. Outdoor temps were in the 50s and 60s and the transmission spent most of its time around 129-133 degrees.
Fueled up just before returning home and the six hour run averaged 13.65 mpg for 285 miles with an average speed of 55.69 mph. Well, that's five hours between refuelings.
Are y'all down a little bit mpg wise too with this cooler weather and E85 or might something be amiss again?
Tonight we had a six hour run and the usual stations were not open. Topped off on the highway rest stop with E85 @ 78% alcohol content and barely averaged 13.5 mpg @ 71 mph. Fired up the Tech-2 on the return leg and could not find anything amiss. She should have seen just over 14. Cats were in the 1300s, downstream O2 sensors steady, upstream moving great but only into the 700s. Occasional torque management knock retard, about every 30-45 seconds, timing was usually 37 degrees. Load was about 100 foot pounds and 55-60% if I remember right. Outdoor temps were in the 50s and 60s and the transmission spent most of its time around 129-133 degrees.
Fueled up just before returning home and the six hour run averaged 13.65 mpg for 285 miles with an average speed of 55.69 mph. Well, that's five hours between refuelings.
Are y'all down a little bit mpg wise too with this cooler weather and E85 or might something be amiss again?
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