Can’t get AEM x series gauge AFR to match Smanager

[joepeace]

I have read many posts with similar issues but none have helped me solve mine. I’m hoping someone can help me out. I have a P72 with Hondata S300 V3 (P72 base map). Engine runs great however I can’t get AFR in Smanager to match my AEM x series wideband.

Wiring is 12v from under dash fuse panel, both grounds( black and brown) to thermostat housing spot (via a additional wire not through vehicle harness) and white wire to D10. Both resisters are cut (136,138), ELD disabled and parameters set for voltage are 0.50v-8.50, 3.00v-14.44, 4.50v-18.00

Gauge works but I cannot get AFR to match Smanager no matter what I do. Smanager always reads about 19’s AFR using AEM voltage settings. AFR does change if I mess with voltage settings but it is closed to impossible to get it accurate or even close. I have changed voltages in parameters to both AEM manual and others from this site, double checked all wires to ECU are in correct pin and all grounds are good. I have even rewired to use analog power and ground with no success.

Testing voltage from gauge to ECU it stays at 4.88 while running at around 13.8 AFR on gauge. It never gets to 5 volts and I don’t see it drop below 4.3volts when I get AFR to change when voltage does change it is very fast and erratic and never outside of what I stated above..

Is my ECU faulty? Am I just dumb? Lol

Please help!!!!

[joepeace]

Last calibration was wrong here is the one loaded currently. No get me close to proper AFR reading in Smanager.

[Spunkster]

It sounds like the gauge itself may not be working correctly if it is not outputting a voltage that corresponds to the correct AF ratio it is actually displaying.

We have recommended the PLX Devices widebands for many years as we have seen them have the least amount of issues. AEM widebands tend to have the most issues.

[joepeace]

Thanks for the input Spunkster! I will contact AEM and see if they can help.

[joepeace]

AEM swapped gauge everything is perfect now.