Lambse? (Tweecer)

[QWKSNKE]

Is this the a/f the EEC is eeing from the O2's?

[Italian LX]

Originally Posted by QWKSNKE

Is this the a/f the EEC is eeing from the O2's?

Damn, I knew I meant to talk to you about something else last night.

. . . After we talked the other night, I surfed the TwEECer board a bit and found some decent information on the LAMBSE. I think I understand it now, but not fully confident enough to post it as if I know the answer.

[Craig K.]

Lambda probe in German is an O2 sensor, perhaps Lamb- is a base word for Oxygen?

[Italian LX]

Originally Posted by Craig K.

Lambda probe in German is an O2 sensor, perhaps Lamb- is a base word for Oxygen?

The way I understand it, lambda is a unit that measures how close the A/F ratio is to stoich for a fuel; a lambda of 1 represents the stoich point.

Lambse is the calculated A/F ratio used by the EEC. It is used to tell the EEC what ratio to shoot for (commanded A/F ratio).

[Sendero]

Originally Posted by Italian LX

Lambse is the calculated A/F ratio used by the EEC. It is used to tell the EEC what ratio to shoot for (commanded A/F ratio).

This is the way I understood it also. Your LAMBSE is what the EEC is commanding for the current conditions and your KAMRFx's were how closely they match your tables.

[QWKSNKE]

guess it is usually off by a couple of points. I noticed that it showed 9.8 a/f on the datalog in the upper rpm and the wideband showed around 11.x at the same rpm range.

[Sendero]

Originally Posted by QWKSNKE

guess it is usually off by a couple of points. I noticed that it showed 9.8 a/f on the datalog in the upper rpm and the wideband showed around 11.x at the same rpm range.

Remember, its no better than a guess based on a number of calculations. (Clint could probably answer this better)

[Italian LX]

Originally Posted by QWKSNKE

guess it is usually off by a couple of points. I noticed that it showed 9.8 a/f on the datalog in the upper rpm and the wideband showed around 11.x at the same rpm range.

What was the fuel table supposed to be commanding at that point?

[86GT]

I thought that I responded to this but I guess not. LAMBSE is commanded AFR. It should match all of the table plus there corresponding multipliers and so on.

When the EEC goes into OL it will use the last known KAMRF. Since your WB and LAMBSE don't match the upper part of the MAF is way out of wack. They should match.

KAMRF stop updating once you go into OL. This is how the aftermarket MAF manufactures make there horse power. They have an accurate curve down low where KAMRF can correct for any problems. When the upper part of the curve is used, it is most likley in OL and KAMRF's are not updates. This allows the upper part of the curve to be set anywhere the manufacture wants without haveing to worry about the adaptive strategy correcting. Usually the MAF manufactures lean out the upper part of the curve.

[93Cobra#2771]

Wow, several days late and a dollar or two short on this topic, since Clint chimed in.

I'll add to Clint's comments and say that if your commanded LAMBSE values are off, then your MAF transfer curve can be off at that same time (KAM must be cleared to verify this, though).

Usually the MAF manufactures lean out the upper part of the curve.

That is what I find funny in internet land. People say "I picked up .2 with X MAF" - without knowing their before and after a/f, they don't know if they picked up power from a better a/f, or from the bigger meter. Usually it's from a leaner a/f...