AEM Uego WB 02 Questions

[mdurbahn]

I finally got around to putting a aem uego i had sitting around from an old project in my 930. It has a out put for datalogging but I am not sure how to do it with this car..ie what software to use.

Secondly I have some really wierd a/f readings...cruising at 30mph i was at 17-18, if I floored it they would go down to about 10.9 when the boost kicked in. Doesn't that sound like some wierd readings?

I am thinking I will need to get a leask or UTCIS adjustable wure to tune this in now..

[930gt-40r]

Im sure your fine with that cruising reading- on boost it sounds a little rich but thats fine. As for the out put I dont know how you would do it- Maybe AEM sells the software for the computer. I have the same unit in my car.

[JFairman]

If the gauge is calibrated and accurate thats good if it's running well, but what is the AFR up around 6000rpm under boost?

[mdurbahn]

I didn't take it up that high, I just drove around the block to see if the gauge worked. Maybe I will wind it out tomorrow and see what if reads.

[BoxxerSix]

Originally Posted by mdurbahn

I didn't take it up that high, I just drove around the block to see if the gauge worked. Maybe I will wind it out tomorrow and see what if reads.

Remove the sensor from the car and plug back into the gauge. Disconnect power from gauge from ~5 minutes, hook back up, and turn on the car with the sensor hangin in free air. Do a free air calibration. Sensor should read ~14.7 after 2-3 minutes. Shut off, let cool, and reinstall sensor.

AEM units are known to be off by a bit. I've installed dozens in various cars and they're always different. Compared to my two known accurate LM-1's here I've recorded discrepancies of anywhere from .1 to ~.9 on the AEM. Has to do with that damn calibration resistor AEM uses in those sensors they give you.

Data logging capabilities just require a basic RS232 software. Blue wire goes to a serial 9 pin connector that allows a cable connection to a laptop or PC for data logging. Also a common 0-5v output that most ever program or EMS uses to compute AFR if needed(white wire)


I should add that you can use Hyper Terminal in Windows to data log this information if needed.

data = 8bits
bps = 9600
stop bits = 1
parity = none

You'll need female 9 pin connector to solder to the gauge leads. Blue goes to pin #2(2nd one in from right on group of 5 on top, looking at connector end) and you need a chassis ground to pin #5(5th one in from right on group of 5 on top looking in from connector end)

[beepbeep]

Do you have air-injection hardware installed on your engine? It will mess upp the O2 readings.

[mdurbahn]

Originally Posted by BoxxerSix

Remove the sensor from the car and plug back into the gauge. Disconnect power from gauge from ~5 minutes, hook back up, and turn on the car with the sensor hangin in free air. Do a free air calibration. Sensor should read ~14.7 after 2-3 minutes. Shut off, let cool, and reinstall sensor.

AEM units are known to be off by a bit. I've installed dozens in various cars and they're always different. Compared to my two known accurate LM-1's here I've recorded discrepancies of anywhere from .1 to ~.9 on the AEM. Has to do with that damn calibration resistor AEM uses in those sensors they give you.

Data logging capabilities just require a basic RS232 software. Blue wire goes to a serial 9 pin connector that allows a cable connection to a laptop or PC for data logging. Also a common 0-5v output that most ever program or EMS uses to compute AFR if needed(white wire)


I should add that you can use Hyper Terminal in Windows to data log this information if needed.

data = 8bits
bps = 9600
stop bits = 1
parity = none

You'll need female 9 pin connector to solder to the gauge leads. Blue goes to pin #2(2nd one in from right on group of 5 on top, looking at connector end) and you need a chassis ground to pin #5(5th one in from right on group of 5 on top looking in from connector end)

Thanks, sounds like I will be able to datalog with this afterall. One question though, are you saying the sensors aem uses aren't very good or the gauge it self? I ask before I am pretty sure the sensor said bosch on it (thought that was a decent brand).

[mdurbahn]

Originally Posted by beepbeep

Do you have air-injection hardware installed on your engine? It will mess upp the O2 readings.

Yes I do, I was going to take it off sooner or later. Looks like I have a good reason to now.

[BoxxerSix]

Originally Posted by mdurbahn

One question though, are you saying the sensors aem uses aren't very good or the gauge it self? I ask before I am pretty sure the sensor said bosch on it (thought that was a decent brand).

It is a Bosch unit, however unlike the Innovative units the AEM gauge doesn't calibrate the sensor being used TO the gauge itself. Rather AEM pre-calibrates the sensors with these little resistor packs in the main sensor electrical connector. As such the sensors are never dead accurate as compared to any of the more effective WB02's. The JAW is even far more accurate than the AEM and just as good if not better than some innovative products.

The AEM is good for a moderate population looking for a much better AFR reading than your typical o2 gauge, however still not quite up to par for major tuning by my standards. AEM really needs to program a free-air calibration mode into the gauge and ditch the resistor packs.

And yes the air injection will certainly throw off the reading by quite a bit. Ditch it and plug the heads.

[930LDR]

Originally Posted by BoxxerSix

Remove the sensor from the car and plug back into the gauge. Disconnect power from gauge from ~5 minutes, hook back up, and turn on the car with the sensor hangin in free air. Do a free air calibration. Sensor should read ~14.7 after 2-3 minutes. Shut off, let cool, and reinstall sensor.

I doubt that you should be seeing 14.7 as a result of performing a free air calibration. My innovate shows 20.8 during the same procedure.

[les_garten]

Hmmmm,
Interesting thread. I was under the impression that Bosch put those resisters in there at the factory. Perhaps we can see a picture. Also, if you are getting 14.7 on room air, call God and tell him "your air" is a little rich, I can hear you slurring your voice from all the Gas fumes, from here, please don't light a match! 20.8 is most likely the end of the voltage scale, I don't have my sheet in front of me of what these read at 5v, which would be dead lean on atmospheric air.

[NathanUK]

Read the post again. The setup does not measure free air like the Innovate.

[les_garten]

Originally Posted by NathanUK

Read the post again. The setup does not measure free air like the Innovate.

Ok, I give up, how many times do you want me to read this...

Remove the sensor from the car and plug back into the gauge. Disconnect power from gauge from ~5 minutes, hook back up, and turn on the car with the sensor hangin in free air. Do a free air calibration. Sensor should read ~14.7 after 2-3 minutes. Shut off, let cool, and reinstall sensor.

[BoxxerSix]

Originally Posted by 930LDR

I doubt that you should be seeing 14.7 as a result of performing a free air calibration. My innovate shows 20.8 during the same procedure.

Ah yea my fault for dubbing it as a "calibration". Has nothing to do with displaying the actual AFR in free air in reality, just a test mode where the AEM gauge detects major lean condition with sensor in open atmosphere and goes into a read mode where it displays 14.7 on the gauge if the sensor is good. If it doesn't the resistor in the sensor is bad/off and the sensor needs to be replaced. It's not the same as an innovative where you must do a free air calibration on the senor prior to first using it.. Just some programming loop in the AEM itself to test for sensor calibration from the get go at least in the ones I've installed in the past.

Still 50/50 on the unit itself. Works ok for the majority of the public I guess but still not accurate enough for my tastes. Fancy import gauge thing to me meant to look pretty in a dash/pod on Hondas and Evos, etc.

[TimT]

AEM pre-calibrates the sensors with these little resistor packs in the main sensor electrical connector.

No the calibration resistor come with the sensor.Bosch installs these.

I was under the impression that Bosch put those resisters in there at the factory

Yes

Lots of info regarding WB sensors on the WBO2 site

More info here

I had a Bosch white paper describing the how they (Bosch) calibrate the sensor. It must be on another pc

more regarding the resistor:

The manufacturing variation problem, which results in sensors of varying sensitivities (differing pump currents for the same Lambda), is solved by adding a calibration component. A resistor (Rcal) is laser trimmed after the sensor is constructed and tested. The laser burns away material and increases the value of the resistor until a standard Ip current is produced at a known Lambda value. If this circuit is reproduced in the controller itself then each sensor will be automatically calibrated without further calibration. Obviously, as each sensor is factory calibrated, and the calibration component is usually in the sensor connector itself, if someone removes the connector, then the sensor has become uncalibrated!

Sorry I cant add anything about operating the AEM UEGO as I've never used one..

back to you regularly scheduled programming

[BoxxerSix]

Originally Posted by TimT

No the calibration resistor come with the sensor.Bosch installs these.....

The manufacturing variation problem, which results in sensors of varying sensitivities (differing pump currents for the same Lambda), is solved by adding a calibration component. A resistor (Rcal) is laser trimmed after the sensor is constructed and tested. The laser burns away material and increases the value of the resistor until a standard Ip current is produced at a known Lambda value. If this circuit is reproduced in the controller itself then each sensor will be automatically calibrated without further calibration. Obviously, as each sensor is factory calibrated, and the calibration component is usually in the sensor connector itself, if someone removes the connector, then the sensor has become uncalibrated!

Ok now that makes sense to me. Never really looked at the other sensors with other widebands, it was just brought to my attention on the AEM units and I assumed it was an AEM thing. DOH! Guess I should pay more attention to my tools and electronics here, hahah!.

[NathanUK]

Originally Posted by les_garten

Ok, I give up, how many times do you want me to read this...

Get it now Les?

[les_garten]

Originally Posted by NathanUK

Get it now Les?

Wellllll... He was putting it in free air. I think it is a mistake for a gauge that reads dead lean to display 14.7, but that's just me and how I roll! Mine doesn't do that, and others usually show 20.8 which is a common number calculated off of the 5v range of the sensor. Mine shows something like EC or some error code

[mdurbahn]

Well I did a little more testing this morning. At upper rpms 5k in boost I am at 10.5 and at 6k in boost I am at 10.0. So it pretty rich, I will leaning it out a quater turn and see what happens.