kamrf's Q's

i have done some research on the tweecer oplink site and actually read some really good threads but it still didn't clarify some questions i have.

1. a really important thing is to get the karmf's to be within +/-5% but is this during just closed loop operation or open,closed and wot?

2.the lambse is suppose to be as close to the actual afr the car is making or is another +/-5% ? also is this at open,closed,wot?

thanks
jake
 
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broken_joke said:
i have done some research on the tweecer oplink site and actually read some really good threads but it still didn't clarify some questions i have.

I'll hit the high points for you Jake

CL is all about the O2's being in control and the load conditions will be in a range of very light (cruise) to a bit more (very light acceleration). During CL the pcm is using input from the various sensors to try and maintain a ratio of 14.7 to 1.00

OL is all about using the fuel tables and the O2's drop out of play during this time. You will go into OL with a load range of say ... about 35% to 100% or greater (WOT).

1. a really important thing is to get the karmf's to be within +/-5% but is this during just closed loop operation or open,closed and wot?

The K's are an indication of the adaptive strategy at work. You tune with the input from the K's during CL only. The K values tell you if you're too fat or lean and the whole thing is based around the value of 1.00 which is considered to be ...... just right.
> 1.00 is the adaptive adding fuel cause you are too lean
< 1.00 is the adaptive pulling fuel cause you are too fat

2.the lambse is suppose to be as close to the actual afr the car is making or is another +/-5% ? also is this at open,closed,wot?

thanks
jake

Lambse is NOT your final air to fuel ratio
Lambse is your commanded air to fuel ratio.
or
Lambse is what the pcm is calling for at any given time. It could be > or < 14.7 due to your tune may be lean or fat at that given time.

The lambse value can be used to help tune during CL & OL.

Lambse values during OL are not as reliable because you got fuel tables, maf transfer, inj settings, and other things that influence the Lambse values.

For a true or accurate OL or WOT final fuel ratio you need a Wide Band O2.

Hope that clears things up a bit for you Jake
AND
if you are trying to teach yourself the basic workings of the pcm

I suggest you go all the way back to the start of the threads on http://eectuning.org for the most concentrated amount of threads that contain the basic info you seem to be asking about.

Grady