when i bought my 98 civic the header was cracked and then it broke the O2 Sensor (engine light came on).. so i bought a ebay header and new O2 sensor but my engine light stayed on...i replace the header and O2 sensor in the month of july and yesterday August 29 i was driving and the engine light started blinking and then my civic was like running on 3 pistons so i went home cause it was raining and the next day i checked my codes and these codes came up (17;vss speed sensor,it works but sometimes dont, 61, 65; wich both are from O2 sensor? and i had 71,72,73 which is cylinder missfire anyone know how it started missfire and what could of done it?

 

There are 2 O2 sensors.

 

yeah i know when i first check my codes for the O2 sensor it said primary one so i change it but now it still says that primary one is not working and theres a other O2 sensor code does the secondary sensor has 2 codes :S lol
i have the codes 61,65
61 Oxygen Sensor, Heated - Sensor 1 (Primary)
high voltage, low voltage, or slow response
63 Oxygen Sensor, Heated - Sensor 2 (Secondary)
high voltage, low voltage, or slow response
65 Oxygen Sensor Heater (Secondary)
malfunctioning or defective oxygen sensor heater

 

Replace/inspect the plugs, wires, cap, and rotor.

Also check whether fuse 15 is blown.

 

i replace the cap, rotor ,wires and plugs and it did the job