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View Full Version : Lambse.. Explain


QWKSNKE
03-28-2006, 07:34 PM
Ok.

On Calcon what exactly is Lambse? I thought it was what the EEC is actually commanding based off the info in the Closed Loop or Open Loop fuel tables?

Am I wrong?

86GT
03-28-2006, 10:37 PM
You are correct. It is the commanded AFR. It is already compensated for the adaptive info in the KAMRFs

QWKSNKE
03-29-2006, 02:51 AM
Why would someone see 18:1 Lambse then? Spoke with a member tonight who is working some bugs out of his car and he said that his Lambse was hitting up to 18:x at idle

Italian LX
03-29-2006, 05:06 AM
Why would someone see 18:1 Lambse then? Spoke with a member tonight who is working some bugs out of his car and he said that his Lambse was hitting up to 18:x at idle
Is his adaptive on? I would guess that his MAF may be so far off that the short-term fuel trims are causing it to comand that ratio. :shrug:

QWKSNKE
03-29-2006, 07:01 AM
I believe adaptive is off. Is there a table that would command such a lean a/f.

Isn't Lambse based off the info you put in either stablized CL and open CL? (What you see is what you command?

93Cobra#2771
03-29-2006, 07:59 AM
I'll wager that adaptive isn't off, or Lambse wouldn't be commanding 18:1. Remember, 14.7 is what the EEC wants at all times. In fact, 14.7 is actually hardwired into the EEC and isnt' changable.

I really have to say that adaptive isn't off at the point where it is commanding 18:1, especially if it is at idle.

QWKSNKE
03-29-2006, 08:23 AM
I'll wager that adaptive isn't off, or Lambse wouldn't be commanding 18:1. Remember, 14.7 is what the EEC wants at all times. In fact, 14.7 is actually hardwired into the EEC and isnt' changable.

.

?? Are you sure? How could you command rich a/f for a combination such as mine without changing it in the fuel tables. That is the only way you would be able to tune your MAF and it have the correct curve.

86GT
03-29-2006, 08:48 AM
There are ranges for adaptive KAMRF and there are ranges for LAMBSE. If you look at the stock ranges for LAMBSE are:

MIN = 14.64 *.75 = 10.98
MAX = 14.64 *1.3 = 19.03

MIN = 1 *.62 *2= 1.24
MAX = 1 *.37 *2= .74

With that said, he could be maxing out the ability to learn and then the EEC is still trying to lean it out further with the LAMBSE.

Sendero
03-29-2006, 08:53 AM
Why would someone see 18:1 Lambse then? Spoke with a member tonight who is working some bugs out of his car and he said that his Lambse was hitting up to 18:x at idle


Mine, with Adaptive on and a stock MAF hits anywhere between 16 to 17:1 at idle. I've tried "correcting" this at least 20 times and the car starts idling rough and die. Same thing with part throttle crusing, I see anywhere from 15 to 17:1 Lambse.

sailorbob
03-29-2006, 04:43 PM
14.7 is actually hardwired into the EEC and isnt' changableThis is not strictly correct, it's possible to set the closed loop AF ratio from anywhere between 29.28:1 and virtually 10:1 if you know where to look in the code.

EDIT: typo fixed, changed 0:1 to 10:1

04 Mach1
03-29-2006, 06:07 PM
My Lambse at idle are around 13.8 to 14.2 if I crack the throttle and hold to 2000 rpms it goes up to 16.8 to 18.1 car starts and idles fine but headers glow. Today I leaned the maf curve 6% ended up with lambse at idle 10.7 to 12.8 at 2000 rpms they sit at 14.67 to 15.3 headers still glow, fuel adaptive are set back to stock setting, oh this is with a 90mm lightning maf.:banghead:

QWKSNKE
03-29-2006, 06:29 PM
but they are only glowing at 2k rpm, right? At idle they are no longer glowing, correct?

04 Mach1
03-29-2006, 06:32 PM
correct at idle its a ok its, just when you crack the throttle alittle

Cougar5.0
03-29-2006, 10:26 PM
Yeah, that leaning out at tip-in drove me crazy. Look at the commanded LAMBSE in the datalog below:

http://home.comcast.net/~ktf23t/wsb/media/52931/site1068.jpg

I ended up forcing the ECU to go open loop sooner to stop the lean bog. I'd love to know the real reason for this behavior. Adjusting the MAF a dozen times did nothing except change whether the KAMRF's were above or below 1. For a moment I thought EGR - except mine is turned off. There is an answer to this - I just don't know what it is yet... :popcorn:

93Cobra#2771
03-30-2006, 08:44 AM
This is not strictly correct, it's possible to set the closed loop AF ratio from anywhere between 29.28:1 and virtually 0:1 if you know where to look in the code.
Expand, please.

Also, how would the EEC be able to maintain the reset a/f correctly? Factory narrow bands couldn't monitor that. It would basically end up as an OL system, right? Or perhaps some type of custom O2, that would be made to target that a/f and allow switching?

Not bashing, just curious how this would be advantageous for someone to change.

Of course, if you ran a wideband O2 and kept close watch, I suppose you could at least make sure you aren't hurting anything, and that your commanded a/f is on the money. But adaptive would certainly be out, and it seems to me that running in CL would be out.

Dale McPeters
03-30-2006, 12:04 PM
Expand, please.

Also, how would the EEC be able to maintain the reset a/f correctly? Factory narrow bands couldn't monitor that. It would basically end up as an OL system, right? Or perhaps some type of custom O2, that would be made to target that a/f and allow switching?

Not bashing, just curious how this would be advantageous for someone to change.

Of course, if you ran a wideband O2 and kept close watch, I suppose you could at least make sure you aren't hurting anything, and that your commanded a/f is on the money. But adaptive would certainly be out, and it seems to me that running in CL would be out.

You are correct Richard the standard narrow band sensor would be worthless
if the code were changed to do this, it would not be able to adjust in the
range required.
However it would be great for open loop type tuning using a true WB O2 sensor.

sailorbob
03-31-2006, 04:45 AM
You're right about needing to change the lambda sensor for a wideband that could run from 10:1 to say straight air (the 29.82:1 is a software limitation).

The software side of things gets more complicated with two things required, firstly where ever the eec is setting for stoichiometric then you need to adjust this for your new desired AF ratio (as an aside, Ford do this on my turbo ecu for some of the self tests and run a AF ratio of 13.97:1 instead of the 14.64:1 I've seen on normally aspirated ecu's and the software must do some adaptive learing inhibiting to maintain it). The second software change is to cope with the different output from the wideband either by rescaling for the wider voltage or adjusting for a simulated narrow band output and accepting for the loss of resolution.

I'm not saying this is particulary easy but it could be done. Dale, I recall reading somewhere a long time ago about someone who rewrote part of the A9L code to use a wideband sensor through the egr input which I guess was for open loop tuning.

93Cobra#2771
03-31-2006, 07:01 AM
Very good - I figured that was what you meant, just wanted to make sure...

Dale McPeters
04-03-2006, 04:56 PM
I'm not saying this is particulary easy but it could be done. Dale, I recall reading somewhere a long time ago about someone who rewrote part of the A9L code to use a wideband sensor through the egr input which I guess was for open loop tuning.

;)

You would be correct.