Thread: o2 sensor issue Retro fit.

Make that 'Clouds' of black smoke when hunting at idle.

On first startup this morning it idled fine in the driveway but as soon as I got on the road I could feel it hunting around even as I was driving along. Accelerating is fine but any thing like cruising at any speed and it hunts and coughs. Slowing down to a giveway or stop sign had to feather the accelerator pedal to prevent stalling, it did stall on me once at a stop sign but started up again easy enough.

I crawled it into the carpark where it idled roughly again but cycled between clouds of black smoke to no smoke at all.
After a minute or so of this the idle came good and I ran out of time.

I think I will have to find the old tune resistor and put it back in for the time being.

The ECU doesn't look for feedback from the O2 sensors until it hits operating temperature, hence why it idles fine in your driveway but when you got it to temp on the open road it spits the dummy.

The voltage sounds completely wrong too. From my recollection it should be from 0-1V output to the ECU, so sounds like it could be wired wrong or possibly the wrong sensors. IIRC the ECU aims to keep the voltage around 0.45 to 0.5 volts so if yours is stuck at 4.68 volts output it will be over fuelling trying to bring the voltage back down (If I recall Titania sensors act in the reverse direction to typical narrow band sensors).

edit* when I was playing with my disco and 02 sensors I wired a switch into the tune resistor so I could revert to Australian tune at any time. Just needed to switch off the ignition, flick the switch, and power her back up again.

Without seeing the installation, It's hard to help.

However a few basic things.

Wire colours are Black=signal
Red -power for heater and sensor
white = heater earth.

I do not know whether the ouput is 5V or 1v as the way I tested mine was to have a Zirconia sensor in addition to the Titanias and use a Jaycar LED mixture sensor LED . I cannot easily find the voltage on the Lambda sites.

If the sensors are running correctly, you will see a very rapid up and down of the LEDs and or voltage which AVERAGE the mixture at lambda. This is very different to a non o2 sensor car which shows a steady LED display of the mixture. It is said that an LED multimeter is too slow to see this and you should use an analogue voltage multimeter.

Have you tried the sensors without the additional link to the gas ecu as this may upset the 14CUX. I also wonder if your car is in "limp home" mode because the MAF is not working. Limp home will give a very rich mixture.
Another thought is a simple one . you do have the correct o2 sensor connected to the correct terminal on the ECU as this would /may cause funny things to happen.( On reflection I think that this is the most likely scenario, unless you have the power etc confused)

Anyway, go back and check everything you have done. It works for me .
Regards Philip A