Sale ends todayGet 30% off any course (excluding packages)

Ends in --- --- ---

HELP! AEM X Series wideband gauge and haltech reading not the same

EFI Wiring Fundamentals

Forum Posts



Tech Articles

Discussion and questions related to the course Motorsport Wiring Fundamentals

= Resolved threads


Hey HP academy,

I thought there was an issue with with my AEM X Series wideband because the output lambda was reading way higher in the haltech software than what the gauge is actually showing. So I went ahead and bought a brand new unit and wired it in and now I'm still seeing the same problem no change.

When the laptop is connected at idle its showing 1.22 lambda on the software wideband channel and the gauge is showing 0.89 lambda. The sensor is calibrated correctly according to the manual for voltage -> lambda. The output reading is showing high 4+ volts but the gauge lambda is correct???

Not sure what else to do... the gauge ground and input are both wired to the haltech harness AVI 6 and o2 sensor ground. Power and gauge ground going to wiring in from the cigarette lighter.

i have been seeing this a bit lately with the AEM gauges can your model be wired to can ?

this could be a better option

Regards Ross

No unfortunately it can't be wired as CAN. I will have to switch to the Haltech wideband controller + gauge which runs about $650 USD.

I would change the calibration for AV input until they match the values shown on the AEM gauge. You probably still have a ground offset. Not sure the o2 sensor ground is the same as Chassis ground that the AEM probably uses.

AEM X-Series Wideband got a separate ground for the 0-5V output signal (Brown wire), make sure it is connected to the sensor ground in your ECU. White wire should be connected to your desired Analog Input in the ECU.

Sometimes, there could still be a slight difference in the reading (+- 0.02), I usually correct that in the input calibration to make them read the same.

Thanks all for the input... I had it wired up as described with ground going to sensor ground on the ECU. I've decided to just go with the Haltech CAN Wideband. Installing it today! Thanks

We usually reply within 12hrs (often sooner)

Need Help?

Need help choosing a course?

Experiencing website difficulties?

Or need to contact us for any other reason?