I have a stock obd0 b16A in a 95 civic ex. I bought the car like that and for some reason ever since I bought it I have horrible gas mileage. I get like 10-12 miles per gallon. On a full tank I only drive about 120 miles. The most I ever got was 160. What can be wrong with car? Is it ECU? O2 sensors? The car runs fine. And no signs or symptoms of the car running rich such as black smoke or gas odor. Help

 

get the car on a dyno tune or wideband to see the a/f ratio.

 

try resetting ecu maybe?

 

Is your check engine light on ?
Is your ecu flashing any codes ?