If I input the calibration given by AEM on my PS1000 the AFR reading is off almost by 2. ie gauge reads 13.0 and haltech reads 15.0.

If I lower the 5v AFR value on the calibration table to 17 AFR instead of 20 by AEM. Then Haltech AFR reading is in sync with the AEM gauge.

Is this ok? is the gauge bad?

 

Email me your map with the calibration you are trying to use. tech@lms-efi.com

I've found the AEM gauges usually need a small tweak. But not nearly that much. They're usually a couple tenths off. Ground offsets can usually lead to a small variance. But not that large. To eliminate the ground offset, I usually try to wire the gauge ground to the Haltech signal ground.

 

If I replace the 17 with a 20 then the readings are off.

 

How do you have it wired? And what is the raw voltage showing at various displayed AFR?

 

12v from the ignition switch, ground to chassis somewhere by the driver kick panel. 5v output goes thru the OEM harness (o2 sensor input) to haltech. 5v output connections are soldered.

 

I just had the same problem, fixed it by running the AEM ground to the same spot as the Haltech

 

Well I fixed my problem by throwing the AEM in the trash and getting a plx wideband.

 

Seems like a needless waste of parts since the problem was a ground offset caused by the gauge being grounded to the kick panel, not the gauge itself.

Any wideband needs to be grounded to the same ground block as the ECU.

 

The PLX is not and I don't have any issues. It was grounded to an actual ground point by the kicker panel.

 

Does the PLX have a separate sensor and power ground? If not, I fear in a short time you'll be facing the same situation as the ground ages a little and the voltage offset happens again.

 

The is what I have



12v and Ground goes to the box and powers the sensor and gauge.