[markymark203]

Two wires were switched at the A plug. Figured it out with continuity. Also determined the sensor plug is faulty by checking continuity through the heater circuit.

 

[R-Civic]

Did you manage to fix it yet??

 

[markymark203]

Did you manage to fix it yet??

Yes, we starting by checking continuity from the plug at the o2 sensor back to the A plug. After doing so, we found that 2 wires were switched. We switched them back and tried to start it. Same code...

We continued to check for continuity now at the actual sensor (both black wires thru the primary oxygen sensor) since we were getting the dreaded
P1166 code for heater circuit. We had continuity at the thru the sensor heater circuit so that determined the sensor was good. Next, we checked continuity from the harness side heater pins and that was good. That told us that my plug was also bad. The pins were pretty corroded and loose. Looks like previous harness owner dragged it for quite some time. None the less, I overlooked that but my electrical guru from Toyota where I work thought otherwise lol.

Magic9won4 hooked me up with a new plug, 12'' of wire and some loom. Should be here tomorrow.

 

[R-Civic]

So beside the bad plug on the sensor, basically the issue was the wires were switched around in the plug?

 

[markymark203]

So beside the bad plug on the sensor, basically the issue was the wires were switched around in the plug?

Yes, wires were switched at the harness side.

 

[Mike@K-Tuned]

Glad to hear you solved your problem Mark. :up:

 

[markymark203]

Glad to hear you solved your problem Mark. :up:

Well it doesn't seme to have been fixed now. Ive gotten the p1166 code to go away and its not stuck at 10.7:1 anymore, but I still have these AWFULLY high A/F ratios, which even adding 10% overall doesn't help! im like 28:1 at idle lol..

take a look.heres the log and kal

 

[Mike@K-Tuned]

Mark,

Sorry I just noticed your last post... Did you sort out your A/F problem yet? LMK

 

[markymark203]

Mark,



Sorry I just noticed your last post... Did you sort out your A/F problem yet? LMK

No. I just deleted the primary and am using an AEM for now. Although, I'd really like to have both as the car will be driven on the street also (not much but still)

It just reads really high numbers. We believe it to be working correctly because after removing it, the car needed to be street tuned.

 

[Mike@K-Tuned]

Hmmm... That sounds like an odd problem.
I have never come across such high A/F ratios with the stock O2.
Unless the sensor or the wiring was the problem.

 

[markymark203]

Hmmm... That sounds like an odd problem.

I have never come across such high A/F ratios with the stock O2.

Unless the sensor or the wiring was the problem.

Weird because I swear they've been checked. Could it still be operational though?

 

[Mike@K-Tuned]

Can't hur't to check over the wiring again I guess...
I doesn't not take long.

Most of the errors I have seen and fixed were due to incorrect wiring.

 

[markymark203]

Can't hur't to check over the wiring again I guess...
I doesn't not take long.

Most of the errors I have seen and fixed were due to incorrect wiring.

Will do..


Sent from my iPhone using Tapatalk

 

[Smitty_Works]

so I did all the checks you said to do Mike. I got continuity at all the proper pins and voltage at the right spots on the O2 plug harness. I triple checked to make sure. I did notice that the #13 pin on c101 and #16 pin on the A plug were missing.

so I fixed that using the other k20a2 harness I had, cleared the code via the memory fuse and the negative battery terminal.

I started the car up and not even 20 secs. I get P0135, again with a brand new denso O2 sensor.

What am I possibly doing wrong here?

 

[Mike@K-Tuned]

What Denso sensor are you using?
Do you have a part number for it?

 

[Smitty_Works]

What Denso sensor are you using?
Do you have a part number for it?

Denso 234-9005

 

[Smitty_Works]

I think I am going to just swap my other k20a2 harness in and see if that makes any difference. if that checks out too I am out of ideas.

 

[Linas]

Hi all,
I have also faced the issue with O2 sensor heater circuit malfunction (code P0135)
So long story shortly:
last summer i swapped JDM K20A to my EUDM ITR DC2. Before I used standard JDM ECU (PRD), standard wide band O2 sensor, K-tuned wiring harness and didn't had any malfunctions.
But, today I did some changes as I need Kpro.
replaced ECU to PRA with Kpro4
replaced O2 sensor to narrow band (from european K20A2 EP3)

and now I have malfunction as mentioned above :/
Any suggestions how to solve this issue are welcome.

Thanks.

 

[Linas]

Hi all,
I have also faced the issue with O2 sensor heater circuit malfunction (code P0135)
So long story shortly:
last summer i swapped JDM K20A to my EUDM ITR DC2. Before I used standard JDM ECU (PRD), standard wide band O2 sensor, K-tuned wiring harness and didn't had any malfunctions.
But, today I did some changes as I need Kpro.
replaced ECU to PRA with Kpro4
replaced O2 sensor to narrow band (from european K20A2 EP3)

and now I have malfunction as mentioned above :/
Any suggestions how to solve this issue are welcome.

Thanks.

no one ???
I did some checks today and figured out that O2 heater relay doesn't clicks as it do on JDM ECU.
Also did some checks according this guide: http://s304.photobucket.com/user/i-...om/user/i-vtec-orginal/media/K-SWAP/primary02sensordrawing_zpsefd5cf94.jpg.html
and pin-outs are as follows:
1-> C302 pin 12 (ok)
2-> C302 pin 18 (not ok)
3-> C302 pin 1 (not ok)
4-> C302 pin 16 (not ok)

So only one of 4 pins is in correct way.

 

[Mike@K-Tuned]

Narrowband and Wideband O2 Sensor wiring is not the same.
Hondata has some info posted in the link below.
Hopefully this is helpful.

https://www.hondata.com/tech-euro-ctr-o2-wiring