My 2005 Civic VTEC has a problem with the A/F Ratio sensor/computer/wiring or something else infuriating. The sensor is dead most of the time and sets P0134. but sometimes it works properly for a short time, according to the A/F Ratio on my Scanguage. The other thing that it occasionally reads around 22-27:1 on my Scanguage for a few minutes, causing the ECU to make the mixture super rich, which makes the car run very rough at idle and seem like it is going to die out. I did a visual inspection of the wires that I could see, and they look fine. I think that there are broken/damaged wires somewhere that are only occasionally making contact since the sensor does work properly sometimes, but then dies or causes a super rich mixture. Could wires look good on the outside, but the copper on the inside is not making contact? The sensor is only about 1-2 years old and it is a Denso, so I doubt that the sensor is the issue. The other possibility is that the ECU is causing the problem, which wouldn't be too surprising since the fuel injector signal wire no longer receives ground pulses, so I had to run the number 1 injector off the number 2 injector signal wire. I can't replace the ECU either because the Honda dealer can't flash it. They said they couldn't get the new ECU to flash, so I exchanged the ECU for a different one at the junkyard that I bought it at, and it apparently still wouldn't flash. I think that the ECU is slowly dying. What do you think about the oxygen sensor problem? How do I figure out what is causing this problem? Thanks!

 

So, because you have one portion of your injector driver output device damaged, you wired in the #1 fuel injector to the #2 wiring and expect the O2 sensor to read accurately ??? This is not going to work. OHM resistance will be altered and the current draw will increase on the #2 circuit... ultimately causing that portion of the injector driver output device to fail as well. You need another ECU and get it programmed to your immobilizer. Per your other thread, there should be NO problem for a dealership to do this with a used ECU.