How To: AEM 30-300 Wideband analog logging via EGR

Finally got my AEM 30-300 hooked up and working after much research and assumptions. I haven?t seen a concise set of directions, so I thought I?d document my trials and tribulations.
My set up is a P59 ECU out of a 2004 Escalade, DBW in a Foxbody swap with a PSI harness, MVPI2 non pro version. There is debate on if serial or analog is better. For me I didn?t want to have an extra connection going to my laptop, so I chose the analog route. I?ve read about Innovate widebands having a problem with analog voltage issue, time will tell if the AEM 30-300 is better.

Step 1 Wiring
The AEM 30-300 has two wires for Analog out, the White wire for Analog 5v signal and a brown wire for the analog ground. On a P59 with the blue/green connectors, the white wire must be connected to pin 55 on the blue connector. The brown wire needs to be connected to pin 41 on the blue connector as well.
On my PSI harness, they have unused pins blocked off with a rubber plug, I guess to keep dust and water out. I had harvested extra pin pigtails from an old harness. If you need some let me know, could drop a few in the mail. Anyway, I took a small drill bit to punch hole in the rubber seal and pushed the pig tails through for 55 and 41. I prefer to solider everything, you are dealing with small voltage numbers so I wouldn?t try crimping any connections it could skew your numbers.

Step 2 Changing the tune
Since the wideband will be logging to the EGR, you need to go into your tune and turn on EGR. I think after 2001 trucks didn?t have EGR so this actually needs to be enabled (Engine> Gas Recirculation>>General). Double check your DTC codes for EGR are disabled or you?d probably throw a code.

Step 3 Setting up VCM scanner.
For this to work, you need to log EGR voltage, add the Channel ?EGR Sensor? , make sure the units are volts. Next you need to setup a user math parameter that will take the EGR voltage and calculate the AFR based on AEM?s formula you can find in the Wideband documentation.
?Tools>Math parameters? Select one of the unused User Maths. I named mine ?Windband AFR? and gave the abbreviation ?AFR?. Take this next line and cut and paste it into the Expressions field. Make sure to copy everything including the open parenthesis

([2811.10]*2.3750)+7.3125

Set the Unit to ?Air-Fuel ratio 14.7 -Gasoline? and the decimals to ?2?
The only place I?m currently showing my AFR in VCM scanner is in the Chart vs Time. Go to your chart layout and add new series or replace one of yours if you are out of space. Make the Label AFR, Parameter, you?ll put the Wideband AFR from the User defined maths you created earlier. Decimals 2, filter 0ms, Max 18 min 8.5. Close the layout editor and you should be done. Save your updated layout so its still there when you re-open VCM scanner

Step 4 Confirm its working
Basically, you will see the AFR chart start running across the screen. If you start logging before the AEM warms up it will be flatlined. Once the display on the AEM is working, VCM should have data in it now. If the chart isn?t showing data from the maths then look at the EGR Sensor channel, it should be reading around 3 volts at 14.65 AFR.

There is more info on this forum and YouTube about taking your AFR and comparing to commanded AFR to dial in your MAF and VE tables.

someone reading my mind, I was just going to ask about this lol. would you by chance know the AFR correction math to get the wideband error ?
This is what I came up with this correct ?
100 * (([2811.10] * 2.3750) + 7.3125 - [501221]) ? [50121]

i did every thing you have posted .can you help solve my problem truck cuts off (while idling )after logging every 15 secounds

Quote:

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Originally Posted by metalmanimal

someone reading my mind, I was just going to ask about this lol. would you by chance know the AFR correction math to get the wideband error ?

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Which wideband error do you speak of? Do you have an AEM 30-300?

This is the math I used, let me high light it above, its kind of buried after cut and pasting it from word.

([2811.10]*2.3750)+7.3125

the AFR vs AFR commanded, this is what im using now and just want to see if it was correct.
100 * (([2811.10] * 2.3750) + 7.3125 - [501221]) - [50121]

I'm not sure. Like I said, there is more info out there about what you are trying to do. This post was simply to help people get the AFR into the datalog in the first place. Goatrope on YouTube has a lot stuff on this subject.

my problem on occurs if egr is enable while logging .if not logging or if unable no more cut offs

Do you have EGR diag enable 0 and disable 255 ?

tww$ You might also want to set your EGR airflow table to all zeros.

Took the car out last night for some data logging and realized the polling rate for the EGR sensor was set really low. Increased it to 10ms, which from what I read is the response rate for the AEM, hopefully that will provide better resolution.

yes

Just chuck will try that today .

thanks yall got it working .got to re do math .I am .8 off lower than wide using the formula listed in original post

tww$ are you using the AEM 30-300? The math posted should be correct. If you are using another wideband, you might have a voltage offset issue. Also turn up your polling speed for EGR to 10hz at least if not faster.

Thanks for posting this! I've been trying to get the conversion to work forever through the AC pressure switch on my 2005 GTO (E40 ECU), and this thread was the ticket. The only change was to substitute the EGR PID for the AC switch (7101)