I cant get rid of this code for the life of me. I need to pass inspection. Im running a d16z6 with a stockp28 along with the rywire obd1 harness. I tried swapping both wires for the HO2 circuit and ground, someone said I could put in a 10ohm resistor in the heater circuit to match the impedence, I did that and it didnt do anything. Any other ideas?

 

are you using the factory o2 sensor clip or are u hardwiring it?

the sensor clip has a certain resistance that the ecu will need to see on top of the 10 ohms consumed by the heater circuit

i think its 1-2 ohms across the factory o2 clip

 

I see, So In that case I should put 1-2 ohm resistors on each wire, since Im hardwiring it? Does that make sense?

 

update..

I purchased a denso o2 sensor, which supposedly has a better chance at being able to match the o2 heater impedance the ecu likes, so I can finally shake this code. However, the wires on the sensor are to short to reach my rywire conversion harness. So, I'll have to make an extension. I heard that this can cause ohm matching problems, in addition to the fact that I'm hardwiring it. Ive also read that the factory connector usually provides about 1-2 ohm resistance all across. Maybe I should get one?

 

K nother update...

I decided against that factory connector idea, as I realized the impedance was not a problem with any other wire ie signal or 12v. So, I started probing the o2 wires when I had the car keyed on again. I was getting around 12v from D22, and A25. The signal wire (D14) was getting around 4 volts, I assume thats bc the car was not on, I know the voltage varies depending on the signal from the sensor. I could not get a volt reading from the heater circuit wire, which is in A6. Is this the problem? What should this reading be? Im pretty sure the wire has good continuity. I know it varies bc the heater is only used during cold starts (it was cold when I performed this test).

cliff notes: how many volts should A6 be giving?
D14 (signal) keyed on, 4-5 volts
A25 (12v) keyed on, 11.80 volts
A6 (heater control) keyed on no reading.
D22 (ground) 12v

 

Despite my best efforts, the code is still there. I dont understand this. Its always code 41. I even tried running the car with NO o2 sensor, ran it for about 10 mins, it did not throw code 1 for the o2 sensor. Could this mean the car is just not going into closed loop? Im going to try running a wire from A6 to the heater line, after that I dunno what else to do. Can anyone chip a P28 so it doesnt run the heater?

 

I ran a wire directly from A6 to the o2 sensor, didnt do anything at all. I also tried probing the heater circuit wire in multiple locations, I cant really get any voltage out of it at all. I also tried another ecu, and the same thing happens. This is insane

 

I totally gave up and Im going to go to the dealer for advice. Theyre going to charge me 90 bucks for "diag" time. Even though I can give them every bit of info they need to figure it out. I feel so dirty....

 

Well I just took it to the dealer and they could do nothing. All the guy did was look at the same diagnostic procedure I had been using! Basically A6 should be giving--or getting (im not sure which) more than 0.1A..I swear I cant get much of a reading at all from the A6 wire, it reads like the ground does which is like 35 mvs..So,..if its reading less than 0.1A they say to replace the sensor....I have a brand new denso in there. So this means what? Is it possible that I overheated the wires during soldering and burned the stuff out??

 

Well I realized, no its really not possible.

Now, for those of you reading this post that have a similar setup (Its a D16A vtec, ie out of a jdm 94 civic ex)...Do you all just have your 4wire02 hardwired, and not not throw code 41? Im running a virgin p28...

 

Well, I know I'm almost the only person involved in this thread, haha--but heres more info

So Im just like not getting anything from A6. My last reading during a cold start was about 0.03 mv...this has to be wrong. What could be going on with my ecu that would cause this? My car idles fine during cold starts..it goes up to around 1500 then slowly settles down...

 

I had the same problem with my crx d15b obdI swap... i kept on getting code 41 so i changed O2 Sensor a couple of times. after messing around with it and the cables i tried on a used 02 sensor from like a 93 Accord. ever since my check engine poped up once with code 41.. i erased the code and didn't come back on since... it's been like 2 months since i swapped out the o2.

 

wow, have you tried another p28 yet? cleared the codes by resetting the ecu? stupid question but are you sure you got the right pinout number from the ecu?

 

Havent tried another P28...I had a chipped PM6 that I used to have in the car so i tried that..Yes ive been clearing the code everytime. And well what Im calling 'A6' is in the exact spot that the rywire diagram shows, so yea Im almost positive its the right pinout...thanks for the responses !

 

Not to really bring anything back from the dead but i'm having this EXACT same problem.

92 cx using rywire 4 wire conversion harness on a jdm b16a and this code WONT LEAVE.

Ive even had the battery unhooked for like 3 days and the mil pops up as soon as I start the car.

New o2 sensor, used the rywire instructions for the rywire harnes...this is getting on my nerves.

I know this is in the 88-91 forum but the eg guy's havent exactly been the best in answering or even giving input...hell, I havent even gotten a response. Thanks in advance.

btw...using the jdm p30

 

I got a 96 del sol S with a JDM D15B swap both OBD2, I got a jumper harness and then a virgin P28.

Same issue! brand spanking new Denso O2 Sensor. I cant shake the code!

 

have any of you tried contacting Rywire for assistance?

 

I dont have anything from Rywire.

 

Only use OEM o2 sensors, those stupid 40 -50 dollar universal o2's will not fix your problem. I should know, i went through 2 denso's and a bosch

 

Ok, well let this scramble your brain then. I still have my OE o2 sensor. It passes well within spec at 13 ohms of heater resistance(where as the universal had 10). Ive diagnosed using the manual and EVERYTHING IS GOOD!!!.

Lol..this is soooo weird. I have signal voltage going from the pcm to the heater circuit, going through the circuit and coming back to the pcm....i'm also getting an o2 sensor (a/f) voltage reading coming from the sensor and heading right to the pcm (like right at 400-500 m/v) on paper...everything should be cool..but i'm still getting a MIL for code 41?

BTW, talked to peter...he's a pretty cool guy. I mean..what can I do? The harness is working for the most part..i dont think the pcm is bad, seeing as this is the only code i'm throwing...i'm stumped. The car starts up and runs fine..the only thing worth mentioning is vtec works..but it doesnt. The car crosses over into vtec but seems to stall and barely creep to 8 thousand...the only thing I can think of is that the car had like 4 month old gasoline(dont ask...I inherited this car, the previous owner didnt care for it too well).

 

Any thoughts?