P0135 Error Code (Primary O2 sensor)
 

I have a 98 Civic DX HB (d16y7). I put headers on this weekend. I got the original o2 primary out, but the 02 2ndary did not want to budge. I cut the wires but I drove the car without the 2ndary o2 for two days...the CEL was on all that time, assuming it was because of the 2ndary o2...I finally got a (bosch Universal - please no flames...I know...I know...go OEM - I dont have $$$). Anyway, I wired it up (i think it's right...if anyone has experience wiring these..please chime in) the CEL still was on..I checked the code...it's P0135 (heater circuit for o2 sensor 1 in bank 1). I reset the ecu (disconnected battary for 5 min) and switched the OEM with the Bosch o2 sensor and put the OEM to the 2ndary harness (basicially flip-flopped), still got the CEL P0135. I want to say that both the original OEM primary and the Universal can't be both bad because wouldn't the code reader throw both P0135 AND a P0137 (or something indicating the 2ndary o2 sensor is bad too)...it just throws the primary.

Also, when i reset the ecu, I turn the ignition to ON (but don't crank it over) and check the code reader...no codes. But when I turn the car over about a second or two, the CEL comes on and the code is P0135. I thought that the code reader will check the o2 sensor even if the car is not cranked over?

Am I missing something??? Is there a fuse or something that may be blown? Or, is there something else that I need to check? I really don't want to spend anymore money on another o2 sensor, because I'm not 100% sure that will cure my problem.

I really need your help...please advise....

my wiring...just in case you see the problem..
OEM wire-------->Bosch Universal
1) Green--------->Gray (Ground)
2) White----------> black (Signal)
3) black-----------> white (Heater)
4) black------------> white (Heater)

Thanks,

Ralph

Re: P0135 Error Code (rviray)
 

ttt

Re: P0135 Error Code (rviray)
 

up...

Re: P0135 Error Code (rviray)
 

help please

Re: P0135 Error Code (rviray)
 

Im having a heater code on my 97 d16y7, replaced sensor with Denso and still has it. With all the combined knowledge on this board, you think some one can steer this post in right direction. There have been numerous posts on similiar o2 sensor problems. Code 61 i believe.

Re: P0135 Error Code (rviray)
 

I was hoping to get some clues to this...I tried to search here and a couple of other honda sites for a push in the right direction....but no go so far. Thanks for the bump 97civicdx!

anyone?

Re: (rviray)
 

What CEL code is it throwing off?

Re: (97civicdx)
 

P0135 for the primary...it shouldn't because that is the OEM one connected to the header...
There is a P0141, for the secondary, but I should expect that if there is no catalytic converter...correct? or should it throw a different error code for that? I have the 2nd o2 sensor in 2nd hole in the header after the primary.
I rented an error code reader from AutoZone and cleared the codes from the ecu....and it still comes back.. I really think that it is the wiring and not the o2 sensor itself...is there a fuse or something that I can check? Thanks for helping me out...

Re: (rviray)
 

no fuses.

My guess is the wiring is wrong. Did you solder the connections? Your best bet would be using an ETM to make sure everything is wired in correctly.

And don't worry, Bosch O2 sensors are great! And a lot cheaper...especially when making a homemade wideband and using a Bosch wideband O2 https://honda-tech.com/forums/images/smilies/emthup.gif

Re: (Emerika)
 

Today, I bought the oem bosch primary o2 sensor (the one with a plug) still got the error...that is why I am thinking it is something other then the actual sensor...

Re: (rviray)
 

reset the ECU?

Re: (untitledsn41)
 

sorry...forgot to tell you that I rented a code reader from AutoZone...it allows you to reset the errors on the ECU....I also did the disconnect battary thing...

When I turn the car on (not crank it over), after a reset, the cel does not come on...when I turn the car over, it takes about 2-3 seconds and the CEL comes on... when I read the code it is P0135 along with the P0141 - thanks for your help