OXYGEN sensor problems

Guys i am throwing a code 1 on my obdII b16a. The funny thing is that sometimes the light will come on as soon as the ignation is turned on and the car not started then sometime after long periods of driving it will then throw the code.
Now a code 1 is high or low voltage from the o2 sensor, if this is the case then how could it throw a code 1 as soon as the ignation is turned on??

Can anyone assist me..

zort

The only way to rule out the actual sensor would be to relace it with a known good sensor.

The thing is that i changed it with two working used o2 sensors and the same thing happened. I am going to change it with a new one to test and will advise.

zort

wheres the best/ cheapest place to buy O2 sensors

The thing with the frist gen B16s is that they came with two O2 sensors, the C8 and C16 plugs i believe. I put a 4-1 DC header on mine, which only provides a place for one O2. I had the exact same problem, the check engine light would only come on random, but the codes flashed on the ECU at all times. The way to fix it is get a universal 4 wire O2 sensor, i paid bout 60$ for mine. There is a signal wire and a ground, and an ignition wire and a ground. Take the signal wire to both the O2 sensor wires. Take the ignition, obviously to the ignition, its on the A plug, don't remember the number off hand. And then just ground the ground wires out and that will completely fix the problem. I know this because I looked all over on how to solve the problme and nobody could help. Finally found the fix online, some guy used a bronco O2 sensor.