Erratic Lambda - M800 with NTK

[fastech]

Hi guys,

I've got an M800 with an NTK o2 sensor (LZA08-H5) directly connected and getting a dirty reading that jumps up and down. I'm assuming there is noise being introduced in the wiring. To possibly save some time i thought i'd see if others have seen this behaviour and have some ideas. Fluctuations change with RPM.

Thanks
Dave

[Stephen Dean]

Hi,

Is this a recent occurrence, or has it been happening for a while?

Have you done a free air calibration on the sensor?

Checked for exhaust leaks before the sensor?

[fastech]

Hi,

Is this a recent occurrence, or has it been happening for a while?

Have you done a free air calibration on the sensor?

Checked for exhaust leaks before the sensor?

Hi Stephen,
Recently changed from M8 to M800, previously had the old Bosch LSM on it. I did try a Bosch LSU first and got strange results thinking the sensor was bad. Decided to go NTK, but now know the old sensor was most likely ok.

I did a free air cal. Sensor is on dump pipe after turbo, used another ntk sensor in cat for dyno (initially wanted to verify accuracy against another) and that's smooth as silk. I'll have to plug the dyno's Autronic into my sensor to verify normal behaviour also in case it was a bad sensor from new to rule out that.

Thanks
Dave

[Stephen Dean]

Hi Dave,

Do you have the Lambda Enable on the M800?