I just did my Civic b18c swap back to a Sohc vtec d16y8. Both engines never had check engine lights on. P0131 code came on and i reinspected the wires and it looked good. I thought maybe the 02 sensor got damaged from storage over the years so i took my good b18c1 o2 sensor and rewired it with the civic connector. same code

the code is o2 sensor low voltage in bank 1 sensor 1. I rechecked my a few times wiring and even tested a second sensor and its still throwing the code almost within a min or two once its warmed. I tried putting in a different ecu thinking possibly i damaged the old ecu in storage. still no luck anyone dealt with this code before and some easy solutions.
I check for exhaust leaks and vacuum leaks that causes a lean low voltage but nothing obvious yet on it.

any suggestions on the next step? no time yet to get it hooked up to my works scantool to see o2 readings.


Modified by NationsMostWanted at 6:06 AM 1/29/2008


Modified by NationsMostWanted at 6:07 AM 1/29/2008

 

your not alone im having the same problem. although i tried a bosch o2 and i got a different code. the p0135 code for low voltage i was told that perhapse the car was running lean but changed reg and injectors allong with fuel filter. still same problem. upgraded fuel pump all BS i ran into this problem after i did a wire tuck and been ratteling my brain for the last 5 months over this crap.

 

did you try reseting the code to see if it pops back up...

 

yeah i actually did a lot of things starting with that. i found that with the stock denso o2 sensor it would come rite back on no matter what but if i changed it to the bosch o2 it would come back on if i drove the car cold but not if i let it warm up first. but when i did that, the readiness codes would not clear out of the computer and i could not get it through emissions that way i also found that if i drove it cold and the light came on i would stop the car and unplug the battery and reset the code. by then the car was warm and the light would stay off. but same result with the readiness codes. i replaced the 15 fuse i re-did the entire fuel system, changed the o2 sensor with another one that came off a different car brought it to two honda certified mechanics. nobody can figure this out i am assuming that it probably has something to do with the wire tuck that i did on the car and am dreading un-doing everything and putting it back to the original state but i have been prety much stumped by this for about 5 months now i just pulled the motor again and put it into a nother car and i am going to try putting a d16y8 back into the car to see if maybe that fixes the problem just to get it through emissions and then putting my race engine back into the car. ill be running aem on it so i will be dealing with a little bit different of a platform by then. i have gotten to the point where i am frustrated now and am thinking maybe last resort i can just swap the stock motor back in and hope for the best......after hearing the entire deal with the car, do you have any thoughts?