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paulg23
03-08-2011, 03:54 PM
Hi - I have put together a wideband o2 monitor. It uses a Tech Edge OEM6 module to control the o2 sensor and my own creation to display the readings. To try and check it out I tried to use it as a tailpipe sniffer but it reads rich all the time. The standard narrow band one is switching between 1v to 0v as it should. I have checked out my software and all seems ok. Any clues as to why it might read rich?

paulg23
03-08-2011, 04:13 PM
4725847259 meant to attach these pictures.

swinks
03-08-2011, 05:58 PM
67.1 AFR???
Are you sure it is right scaling?

paulg23
03-08-2011, 06:09 PM
67.1 is in free air. According to tech edge the module has a range of 7:1 to 73:1. With the engine running and the narrowband doing it's stuff my wideband was reading 11:1 at the tailpipe.

swinks
03-08-2011, 07:55 PM
Typical wideband scale is from 7 up to 22.5, anything more is displayed as o2.
Can't see any point to measure anything above 22:1. Your device seems to me bit weired and odd :coat

paulg23
03-08-2011, 10:29 PM
From what I read most o2 sensors can detect AFRs as lean as 200:1 but the controllers and displays we usually see are limited to around 22:1 as any higher is pointless for automotive use. I can limit it to this easily enough but wanted to make sure it was working as it should first. Can't find any info on what effect running them too cool has. It is heated but perhaps it needs to be further along the exhaust to get up to proper temperature. Just wanted to make sure it was OK before removing the narrowband and fitting this in it's place.

paulg23
04-08-2011, 11:29 PM
Sorted. The Tech Edge website isn't very good. Reading correctly now.