AEM 30-2300 UEGO 0-1V output question

[sparky]

I have installed an AEM 30-2300 dual channel UEGO. I will be using it in wide band mode with AEM ECU, but first I want to run my stock ECU using the 0-1V outputs. Problem is the car does not drive properly using 0-1V and starts to misfire after a while, although I get no ECU check engine codes (in 15 minutes driving).

When I read the output voltages with engine warm and at idle I get following readings (from both channels):
0 - 5V = 4.1 - 4.3V
0 - 1V = 0.69 - 0.7V

(note: I have both OEM and AEM sensors installed in the exhaust, and these measurements were taken with ECU using OEM sensors, AEM not connected to ECU and reading AEM outputs using a voltmeter)

The 0-5V values looks about right, corresponding to an AFR of about 15.2 based on tables in AEM install notes.
But the 0-1V reading seems to be in error, corresponding to an AFR of about 12.3 based on same tables ?

More confusing is that a normal O2 sensor should output around 0.45Volts at lambda = 1 or AFR 14.6. The AEM install notes has two graphs, one with this value (450mV) at lambda 1 and http://en.wikipedia.org/wiki/Oxygen_sensor confirms 0.45V as the target value, but the other graph and the tables in the same AEM note expect 0.57V at lambda 1. This seems to be inconsistent ??


Is the 0-1V channel meant to mimic output of a normal oxygen sensor?
If yes, why does lambda 1 = 0.57V and not 0.45V ?
If my AFR at idle is around 15 why doesn't the 0-1V channel read around 0.55V ??

Any clues appreciated.

 

[sparky]

bump - no AEM gurus out there ?

 

[DDozier]

This has been documented in the AEM forums, I remember reading it but I can not find it. Either way what you are trying to do will most likely not work. AEM says the 0-1v output is used to simulate a narrow band O2 but it will not act like a normal narow band O2. A normal narrow band O2 will look like a fast moving toggle switch to the ECU toggleing from rich to lean very rapidly at the 1 Lambda point the AEM will simply interpolate the 0-5 wideband signal into a 1v range and as a result the scaling does not mach up as you have found. Some other widebands allow you to program the 0-1v output to your needs changing ramp rates around stoich and voltage at stoich point but this is not available on the 2300.

Untill you change your ECU you should run both O2's the OEM narrow band O2's connected to the OEM ECU and the AEM widebands to a gauge or logger. Once you change to the AEM ECU, you should remove the OEM sensors and plug the hole and wire only the wideband 0-5v output into the ECU O2 sensor inputs.

As far as I know there is no way to make the 0-1v output work with the OEM ECU, maybe someone else has figured out a way to make it work but there are no setting to program or way to adjust the 2300, its outputs are what they are.

FYI: The Zeitronix ZT3 and ZT2 allows for a configurable narrowband output
http://www.zeitronix.com/installation/Zt-3 Instructions.pdf

Dave

 

[sparky]

Darn and double darn. I guess that explains why the AEM staff don't buy in to my queries on their forum.

But thanks DDozier, a least now I can stop chasing an impossible solution. Makes me wonder why they bothered producing a 0-1V output if it doesn't mimic normal narrow band ???

 

[DDozier]

Darn and double darn. I guess that explains why the AEM staff don't buy in to my queries on their forum.

But thanks DDozier, a least now I can stop chasing an impossible solution. Makes me wonder why they bothered producing a 0-1V output if it doesn't mimic normal narrow band ???

That may also be the reason they no longer have the 0-1v output on any of the new UEGO widebands.

Dave