Recently my gas milage has dropped from 28 in town to around 23 and from 34 highway to 30. It is a 98 Venger with the 420A and 5 speed. Recent change of plugs, wires and induction cleaning has not helped. There are no engine codes and the car is running pretty good except I can smell that it is running on the rich side. I recently had a cracked vacuum line on the EGR system and a failed coolant hose that blew out causing a near disaster but everything is working fine excpt for the gas milage. The engine has 249K miles on it and it does use about 2 quarts of oil every 5000 miles or so. A friend told me to change the oxygen sensors? But I am not sure what to do. Could this just be due to the increase of ehonal in the fuel?

 

Low gas mileage can be clogged fuel injectors or bad O2 sensors ... when mine declined sharply I bought one and tried it in each position till it got better ... Unfortunately there is no CEL that says bank 1 ... At least you have a 50/50 chance

 

I will give the O2 sensor a try. then fuel injectors. Other than bad gas milage and the rich smell of the exhaust the car is running awesome [especially for a car with 249K miles on it]