1996 1.9L Escort, Dropped fuel economy, CEL code P0170. Could it be Oxygen sensor?
Its Ford Escort LX Wagon automatic transmission 1996 model. Fuel economy has dropped from 22mpg to 15mpg. Check engine light is on and error code is P0170. A friend who is familiar with Fords says it must be O2 sensor but is not sure if its front or rear sensor. He says it cant be vacuum leak or MAF sensor because there would have been additional OBDII codes if any of them would be a possible case. Am trying to save some $$, so wanted to ask here what sensor do you feel it could be?