Code 43

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Slow&Delirious

isn't fast or furious
I recently did a tune up on my D15B, everything is Factory except for a short ram intake. I changed plugs, wires, and the fuel pressure regulator all with OEM parts from the local AutoZone. I also just installed a 4-2-1 header when i did all this. Now i am getting a Code 43 after a few min of driving. I have done my research and code 43 is a Fuel supply system fault. Meaning im too rich or too lean or perhaps a fault in the H02 sensor. Google was not much help with a code 43.
The only thing i can think of is when i first installed the header i put the H02 sensor in the hole in #1 cylinder header pipe because the wiring wouldnt reach to the second hole down where all the pipes collect before it reaches the Cat. It makes more sense for the 02 sensor to read all the cylinders rather than just #1 so after getting the code a few days in a row i extended the wires and put the sensor futher down stream right before the cat but it had no effect on the CEL comming back the next day

any input would be helpful. i dont know if i need a new O2 sensor or perhaps the autozone FPR was bad. But the plugs are gapped correctly and it idles and runs fine with plenty of power
 
I have read that this code can be set because of a fault in the Heater circuit in the O2 sensor. I will try and test mine later, if im not mistaken the 2 black wires are the heater circuit and should have 15ohms of resistance.
I have also read about the brand names of O2 sensors, honda wants 210 bucks which is too rich for my wallet. I have read that Bosh O2s have super short life and the closest sensor to a honda one is a Denso, which i have read good thing about. Can anyone confirm this or have their own oppinion?
 
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Bosch is hit or miss it seems. I had the heater circuit go out on 3 of them last year and yet the one I bought 3 years ago is still going strong. Although Autozone gave me a 12 month warranty on them, so its not like replacing them was a hassle.
 
Intermittent is what im getting
I think its the O2 sensor, sigh, but since it drives fine im just going to put it off till it goes bad
oddly enough i think it has to do with temp, if its freezing outside it always comes on, if its above 50ish the chances of it coming on are slim, and just cycling the key turns the light off but its still stored. But i couldnt get the light to come on in the driveway, even after 20min of it warming up
 
is this on the '01 civic or the del sol? if its on the del sol, instead of spending money on a new o2 sensor, send your ecu off and get it chipped with a map for your engine, get them to disable your o2 sensor, and be done with it. also, if your original fuel pressure regulator was okay, try putting that back on and see if that helps before you chip the ecu.
 
bosch o2 sensors are available with longer connecting wires for like 10 bucks more than the one you probably bought. you extended the wire yourself...did you solder the connection? crimp it? or just twist another wire to lengthen your wire and use a wire nut to hold it? the connection has to be done correctly and the gauge wire you used also has to be correct. i see someone posted a page from ALL-DATA for you but i'm not sure if its correct for your car. you didnt really say what car model and year you have. if you did, i must have missed it. what model and year is your honda? i have an ALL-DATA account and i used to work as a certified honda tech in the dealerships. i'd be happy to try and help you if i can. and if you havent given up on it yet
 
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