I put E85 gas (85 percent of ethanol and 15 perceent of unleaded) in my 1999 Ford Ranger with 3.0 liter FFV ( "V" in VIN number 8 charater) and ran stronger but the mpg dropped to 9.5 and "engine check" light came on, AutoZone plugged in my Ranger with code scanner. it show 171 and 174 ( too lean in bank one and too lean in bank two) I already replaced fuel filter in just one week before I first put E85 gas in. I wonder if poor mpg could cause by bad DPFE sensor or bad fuel sensor in tank ( if I'm correct that FFV should have a fuel sensor? ) I wonder if fuel sensor reading E85 came in the tank then it will send a signal to PCM, so the PCM will control air & gas mixture on fuel injector and control the timing to help to stop the lean and mpg got better. am I right?
I know E85 is 20 percent less mpg but should not dropped by 50 percents! ang suggest? it would be helpful. John