Wideband->Narrowband Problems

[tdonnell]

Hello again everyone,

I posted a topic about this in NA tuning but nobody responded so I will try here.

I bought the PLX M-500 Wideband o2 kit with datalogging. This unit can supposedly trick the ecu into thinking it still has a narrowband sensor.

In the instructions it says to wire two 10 ohm, 10 watt resistors in series into the o2 heater circuit power and ground, but according to my Chilton manual's wiring diagrams (which are probably wrong), there is only one marked wire for the o2 heater circuit, and it is designated "o2 heater control circuit". Anyway, I just wired both of them into that wire alone, and I am getting a CEL for malfunctioning o2 heater control, and low o2 voltage.

My question is: does anyone know which wire or pin's are for the o2 heater circuit power and ground? Or does anyone know which of the wires in the engine bay in the stock o2 harness control's the heater circuit? There are two grey wires, one black wire and one white wire going into the stock o2 sensor harness that is disconnected. But as long as I can put resistance into the right wires to let the ecu think the stock o2 sensor that isn't there is being heated I will be alright. Whether or not it is done at the ecu.

The low voltage code I am not sure about, if it does not turn out to be the resistors that are wired incorrectly, I would consider it being the "noise filtering capacitor" that I wired up between the o2 signal wire and the o2 ground at the ecu. The M-500 also has a narrowband output wire that is wired up to the o2 input wire.

I know JonGTR has an M-300, so I know this can be done.

This post has to be somewhat confusing so if you need any info just ask.

Somebody please help me!:depressed:

Thanks

[4doorGL]

Not sure. I'll keep my mouth shut about how easy it is with the FJO though :P.

[Blacktibs]

Hey Rob, I had a few questions to talk with you about, sorry to jump in on the forums but I'm going to try to give you a call. I'll edit this out as well, maybe add something useful to the topic, lol.

[tdonnell]

LOL! I still stand by my decision to go with the PLX unit though. I have it setup so I can wirelessly view and datalog in real-time my o2, MAF, TPS, RPM, and AIT. The FJO cannot datalog or view that many channels at once.

Although the FJO is probably easier to install, it cannot do as much. And the only reason I think I am having a problem is because I cannot figure out which pin or wire is the heater control ground wire. If I figured that out it would be a simple task to fix it.

Any other help is much appreciated. Where is JonGTR?? He could probably help me more than anyone.

Thanks again everyone

[JonGTR]

Sorry man, I'm using the stock o2 sensors for the ECU and running the wideband on it's own. I've never really tried getting the ECU to read the narrowband output on the PLX.

[tdonnell]

Thats cool. I appreciate the reply, I think I am just going to do a trial and error test. I will just install the resistors between the black wire and all three of the other wires that run to the stock o2 sensor (in the engine bay). I will just have to wait a day or two after doing the swap to see if the CEL comes back on. Although I still have the low voltage code to deal with, I think that is from the noise filtering capacitor that I installed. I think I am going to take that out and see if that solves the problem. Well, I know what I have to do, now I just have to get around to doing it lol. I hardly have any time with work and all. Thanks for all of the inputs guys.