I am using rom 88590015 and evoscan v2.9. I have wired the white wire from my aem 30-4100 digital wideband into pin 73 on evo 9 USDM ecu. My eval values are just like they are in the tutorial and I am getting readings between 9-10 when the actual gauge is reading between 14.5-15.5 at idle. Using request ID 3C and eval right now is 0.03913*x+9 . I checked the voltage the pin 73 and with key on has about 2.15-2.20 volts. Also I have the complete 02 rear sim patch for this rom installed on the ecu. Anyone have any ideas how to get this to display correctly in evoscan? Thanks

 

You might have to adjust for groubd offset. Add approximately the difference between your serial display and analogue .

Mine changed frequently and I'm switching to serial logging

 

so find a differnt spot for the ground for my gauge?

 

See if it makes a difference. The last number in your formula is the ground offset .. You might have to say add 13 instead of 9

 

ok changed it to 13 and now it just goes between about 13.2 and 13.8 and thats revving it up and letting it idle. afr on gauge will got all over but evoscan stays between those numbers..i changed out the ground location too

 

I had to adjust for my AEM. It took a bit of time to get it where it was logging the same.

 

whats your eval look like?

 

03913x+8.4

 

bump for any help

 

Dealing with this same problem, I've adjusted the ground offset from 7-14 and still can't get an accurate reading. I'm in the process of switching to serial logging as this method seems to be hit or miss with most people.

Free bump for a solution..

 

I think I may have figured it out. I was using a rear o2 patch which has a sub routine. is it possible that this sub routine is the reading evoscan is showing?

 

Are you using the 0-5V output from your AEM? Here is what I did with no issues.

https://www.evolutionm.net/forums/8968359-post376.html

 

yes I am using the white wire 0-5V, not the blue data log wire.

 

And thanks for the post. I think I may have found my answer. Gonna try this patch

https://www.evolutionm.net/forums/ec...o2-system.html

 

Well non of those patches seem to work. I spent quite a few hours on this problem and have ruled out quite a few things. Right now my main problem is with the sensor unplugged, and just the 4 pin connector (power ground serial and 0-5v analog plugged in, the gauge will display 14.8 AFR. So the gauge is working properly. When I go to take the voltage reading from the 0-5 analog wire, it should read 2.4 volts roughly, but I am only get around 1 volt. Is it possible my harness is bad? I bought this brand new and the 4 pin harness has never been exposed to any outside chemicals and what not, its been tucked up under the dash its entire life. if anyone has any suggestions or has experienced the same problem, please post up what you did to solve this. Otherwise, I will most likely have to order a new harness and go from there. Thanks