hello I have a 1991 Honda civic dx that has a D15B in it (DPFI) been having issue with hunting idle and rough idle keeps throwing a code for the o2 sensor I replaced that and the code comes back after 10min of drive time after I cleared the codes. I also cleaned the IVAV and replaced the cap and rotor also plugs and wires and coil. so if anyone can help me with this would be awesome this car gets me to work.

 

Check for vacuum leaks to the line going to the MAP sensor. It'll cause the car to run rich which fouls the 02 sensor and drops the idle.