parasonic

Hey guys,

I installed a Zeitronix ZT-2 wideband today and am having problems with the ECU thinking that the heater is disconnected. I tried connecting two 10-ohm 10-watt resistors in series between pins PHO2S and SG1 on the ECU but had no luck. I also tried connecting the heater of the old O2 sensor to these pins and had no luck. My ECU is forcing open loop right now, which sucks, because I am losing 5-7MPG. Any ideas?

Thanks!

Team RS2

you have a wideband which leads me to assume that your turbo or highly modified which leads me to assume you have some sort of tuning software, dissable the o2 sensor via your tuning progrman

otherwise just replace the factory o2 sensor and sell the wideband only advice i got

parasonic

No turbo, I just want to get my AFR to 16:1 at cruising speed. I am using a stock OBD2B ecu. My wideband has a simulated narrowband output, which should be fine.

All that I should need is to have a dummy load similar to the old O2 sensor in order to fool the ecu into having a status of the O2 sensor being present.

EE_Chris

One pin you used is right. SG1 is the ground for the MAP sensor...hint hint.

How are you going to get your AFR tuned to 16:1 and keep it there on a stock OBD2b ECU though?

parasonic

Sorry, I was using SG2, which is the green/black wire. I did not try SG1 because it is for the MAP sensor.

The weird thing is that I just closed the wiring back to the original O2 plug socket and stuck my resistor between the white/black and yellow/black pins, and no more CEL! Somewhere along the line, if you trace the yellow/black wire, it goes through a connector in the engine bay and becomes white/black, and then I lose it as it comes in through the driver's side... (if I traced properly)

Whatever, now I need to find a dead O2 sensor to salvage its connector as I don't want to cut into the wiring harness anywhere other than the one spot next to the ECU. I have a hard enough time keeping track of modifications as is...

So for faking out the ECU, I am only hoping that I can trick it for a while using a VAFC2 and false O2 readings, which can be user-set from the Zeitronix box. It's just an experiment, and if it doesn't work, I will go with Uberdata.

My top priority is to keep a setup that allows me to plug in and get my car smogged, and I needed to get this O2 heater thing figured out before anything else. If I do Uberdata, I will just swap ECU's, but any CEL disqualifies me from emissions in the state that my vehicle is titled in...

EE_Chris

SG1...SG2...doesn't matter, because both are wrong. The ECU controls the ground side of things.

parasonic

Yes, and the SGx pins are ground pins on an ECU-based voltage source.

EE_Chris

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by parasonic &raquo;</TD></TR><TR><TD CLASS="quote">...an ECU-based voltage source.</TD></TR></TABLE>

I'll try again:

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by EE_Chris &raquo;</TD></TR><TR><TD CLASS="quote"><FONT SIZE="3">The ECU controls the ground side of things.</FONT></TD></TR></TABLE>

If you've got one side of the heater connected to the ECU (PO2SHTC) and you've got the other side connected to SG1, then can you see the problem now? No? Then pick up a Helms.