MoTeC Global Forum

Dear,

Is the Ipn vs lambda table different for LSU 4.0, 4.2 and 4.9 sensors?
I now use the table generated after the conversion from ECU manager V2.3 to V3.5.

Thanks,
Ron

The table is the same for all sensor types. If you want to check that the table is correct check that it has values as shown in the help file:
Ipn -5.000 -4.000 -3.000 -2.000 -1.000 -0.500 0.000 continued...
Lambda 0.673 0.704 0.753 0.818 0.900 0.948 1.000 continued...

0.500 1.000 1.500 2.000 2.500 3.000 4.000
1.118 1.266 1.456 1.709 2.063 2.592 5.211

Hi Ross,

If I compare these values with the ones Bosch provides for the lsu4.9 sensor 0-258-017-025 they are way off.
See: http://www.bosch-motorsport.com/pdf/sen ... /LSU49.pdf

I also found values for the lsu4.2
See: http://www.not2fast.com/instrumentation ... nglish.pdf
They are also a little different.

Is this because they are not measuring in real exhaust gas?

I have also problems with the OEM BMW lsu4.9 sensors, they are very unstable (noisy).
The lsu4.9 sensor 0-258-017-025 is much less noisy!

Would it be possible to use the OEM sensors, or do I have to change to the 0-258-017-025 sensors?

Want to use the lsu4.9 ones because of looming issues (and lower heater current, I use injector outputs for the heaters), in the past I used lsu4.2 VW sensors (sometimes I get over current errors when they are cold).

Thanks,
Ron

Hi Ron,


Yes the OEM BMW sensors work okay, but when you try and AIR CAL them they can be a nightmare. The cal number would sometimes change almost 500units per second and will also go negative

Because of this problem Ive moved to the Bosch 0 258 017 025 Bosch LSU 4.9 which works very well. Ive also found the 4,9s to be the most resistant to leaded fuels.

Where are you situated?

Ipn is Normalised Pump Current, not raw pump current. It has a correction applied to it which is dependant on the sensor being used as well as a gain based on the resistor calibration value. So we can use the same Ipn - Lambda values for all supported sensors.