How do I diagnose my fuel economy problemI have dual 100 gallon tanks on a 2009 kwt660. When the red light comes on at the gauge near empty I can only put in 120 gall...
Answer to: How do I diagnose my fuel economy problem2009 Cummins ISX 400 ST.
Answer to: uneven fuel return, 2010 kenworth t660, 450 ISX cumminsI have dual 100 gallon tanks. When the red light comes on near empty I can only put in 120 gallons max. Also after 150 miles of driving a quarter tank will be depleted from the information on the fauge. The Ecm says I'm getting 7 miles to the gallon. The math I do says six. But using both those numbers I cannot match the gauge readings to the mpgs. I already had an overhead done and a new dpf installed. What could it be? Fuel restriction, sending unit, gauge calibration, or bad engine?