lambse, kams... rich?

Discussion in '1994 - 1995 Specific Tech' started by Mustangless, Nov 6, 2007.

  1. My thoughts as well :D

    You want to tune for each SEPARATELY and DIFFERENTLY :Word:

    Making a change to the ENTIRE curve :eek:

    It might can help one :nice:
    It will almost certainly ... H O S E - U P ... the other :notnice:

    I would respectfully say :)
    Get back to the basic info on ... How The PCM Works ;)

    It is difficult for one to improve on a thing :bang:
    One might possibly not have a grasp on :shrug:

    How the thing works in the first place :crazy:

    Stick with it :banana:

    You can do it :Teh-Win:

  2. Got the new tune loaded and had my lambse pegged at 18.30 most of the time. Tried raising my high slope from 40 to 42.5 and was still like that.

    Put my old maf curve back on and it is much better. Now my lambse is 14.4-16.0 and my kams are .91-1.013. EA said to raise my high slope to 43.5287.

    Now with the questions. Most of the time my kams are below 1 and lambse is 14.4-16.0 during CL until I come to a stop. That is when my kams go above 1 and lambse at 13.3ish. It is also wanting to die when this happens.

    Should I lower my low slope some? Doesn't the low slope rich/lean the idle?

    Also, now with my new tune I have a hard start. I am pretty sure it is flooding because I see smoke when it does start. :nonono: I can't say for certain, but I think this is only a problem after it is warm. It did not give me any problems this morning starting (32*) but when the ect was 115 is when I had problems)

    Would crank_fuel_modifr_for_start be the problem for this? Or is there something else that could cause this? :shrug:
  3. Some general info :)

    Low Slope is used at low maf volt conditions/lowest part of the t curve

    High Slope is used when you get higher up in the t curve

    At idle ... you now see ..............

    K's >1.00 so it is adding fuel
    The lambse is commanding fat ratios (<14.7 to 1.00) of around low 13's

    See how those two things go hand in hand ;)

    Sounds like you need to lower the low slope a bit

    I know what you need to do to help with the hot starts :)


    It seems that some of those functions and table names were changed in the
    newer software :(

    In the old software I use a table called fuel_table_startup_OL

    never the less ... whatever they call it these days

    Basically ... the startup table is based upon ect and time

    The values in the startup table are subtracted from the normal table
    thus making things fatter. As time expires ... the mixture becomes
    leaner until you slip into Closed Loop.

  4. I was thinking I need to lower the high slope, but EA was not saying anything about it. Wes told me to try messing with the battery offset some, so I am going to try that. If that does not work then I will lower the low slope alittle.

    Also, that table you are talking about is called "Fuel - Open Loop Startup" aka FN1361. I changed it back to the one I had on my previous tune. I will try to get more logging tomorrow.

    I will probably have more problems by then too. :rolleyes:

  5. Looks as if you are making some progress :nice:

    Yes ... the offsets could make a difference

    They mainly give you some fine tuning ability for different inj behavior when
    a heavy load draw in current is encountered like on a rainy night when you
    would have the ac (defrost), headlights, wipers, etc working.

    You also might need to up the flow on the t curve points for enrichment
    at and around idle ... but ... before you do that

    A good rule of thumb for stable CL tuning is to ......

    1) use as close to known t curve you can find for a start
    2) use low/high slope, min inj pulsewidth, breakpoint, and offset values to
    get K's all up and down the CL range of operation close to the 1.00
    benchmark value.
    3) finally ... a little tweec here and there on the t curve might be needed

    I found a middle ground approach on the offsets was best for me ;)

    By that I mean ... I picked a selection of accessories that was kinda average
    and made sure I tuned each time using the same selection.

    As for the hot starts :)
    I never did any kind of datalogging :shrug:

    I just did some common sense kinda tweecing :shrug:

    I used the thinking my 30's were a certain % size larger than the default
    24# size used in the j4j1 and reduced the values by that amount.

    I also hosed around with the temps and amount of time a bit.

    I might have some of that stuff on my site but I just can't remember

    If the screen shots of that table are not displayed along with the text of
    tuning tips ... I do know you could download the shots which displays
    comparisons of an unmodified j4j1 and one of the last files I made.

  6. okay, put in my new tune drove turned it off. Came back 4 hours later and it started right up. The cars temp was only 100* so that is probably not considered a warm start.

    Did a long log, mostly stop and go traffic. Go to put my info into EA for injector slopes , but I did not datalog the right stuff :nonono:

    I could calc. a new injector slope, so I went ahead and did that.

    1) use as close to known t curve you can find for a start > I think the one I have now is right.
    2) use low/high slope, min inj pulsewidth, breakpoint, and offset values to
    get K's all up and down the CL range of operation close to the 1.00
    benchmark value. > this is what I am going to work on. I think you said to only change high/low, breakpoint, or offset at once, so I guess logging just for offset is okay.
    3) finally ... a little tweec here and there on the t curve might be needed > we will see when we get there.

    Anyways, I did not really run anything for my offset. I cracked my window, and that is about it other than driving.

    My kams stayed below 1 unless I was parked, then it was 1. It looks like when I am stopped my lambse is 13.2-15.0. During acceleration my lambse gets up as high as 17s.

    I will enter my new offset and try to log the right things next time. Then maybe I will be closer on high/low.
  7. EEC Analyzer is sure to explain dialing in your inj's better than I can :D

    I will share some random stuff
    You might wanna break out the :popcorn:
    I might get a bit wordy here :rlaugh:

    I kinda look at working with the slope values as :shrug:

    Low for idle and just off idle driving conditions
    High for everything above that

    BUT .......... never forget ;)
    you really can't go all that high before you slip out of CL

    Also ... if you change just the low or high slope ... you will see things
    are effected on the other side of the breakpoint. More change closer
    and less change farther away you could say :)

    I see the breakpoint as a way to kinda influence the transition between
    Low Slope and High Slope operation

    The offsets can be effected by M A N Y variables :Word:

    Always ... Always ... Always ...................... Remember This :D

    You have datalogging at your disposal :banana:
    The smart cookie kinda guy will use it to his advantage ;)
    Sooooooo ........... USE IT :spot:

    I can use the offsets to give you a good example of how datalogging can
    be such an EYE OPENER :crazy:

    Here is a little story showing some things I discovered ......... :)
    the hard way ........ :rlaugh:

    I had been working on a CL tune for a while and was getting within
    3% all up and down the line on my K's.

    I had been doing my test runs in the late afternoon before dark

    I made a run one evening a bit after supper and on the last half of my
    15 minute run, it started to sprinkle.

    I was shocked to see my K's were way off from the tight 3% results
    I had been seeing :eek:

    I threw the dlog in Excel for some really close scrutiny :nice:

    I was able to see the headlights changed things a bit
    It was the windshield wipers that made the K's really take a dump :bang:

    This made me put dialing in my injectors on hold for a while and pursue
    what I might see during different conditions as far as battery voltage
    was concerned.

    By datalogging, I could see the amount of battery voltage drop various
    accessories caused.

    By datalogging, I saw the battery voltage did not stabilize from a cold
    start until between 20 to 30 minutes of operation.

    See how the ability of datalogging allowed me to use hard data to tell
    me why and how things could change :nice:

    A lot of peeps might not get all that involved and I'm not saying they
    should ... but ... I just like to see what make things tick :D

    Story over and back to your Q's and concerns !!!

    The deal about changing both low and high slope together

    I did it all the time when I was far away from getting things close
    I usually did only one at a time when I was fine tuning

    The deal with CL tuning is so many variables can hose up your efforts :notnice:
    You wanna be focused and keep the variables to a minimum :nice:

    I'd use the t curve you got now
    I'd use offsets for what ever size inj's you now got

    That right there gets two variables out of the picture ;)

    Then ... I'd strive to get the K's to a range of 5 to 7% total variation for a
    rough tune. You will use the slopes and bp for this.

    I found I could get to this point fairly quickly by doing a run of 15 minutes
    after a pcm reset to get some reference points for the adaptive strategy.

    During this first 15 minutes ... I did not gather data but I did keep an
    eye on the real time values.

    After that first 15 minutes ... I duplicated the run again gathering data

    This would allow me to see trends with the adaptive strategy :Word:

    I repeated this procedure until I got the K's to that rough range I spoke
    about above.

    As you get closer ... or ... the range of where K variation diminishes ...........
    You will have to do two things to be more accurate
    1) Allow the pcm more time to get reference points
    2) Gather data over a longer period of time

    Of Course ... if you just datalog longer after a pcm reset ... 1 & 2 will
    be captured all together on the same dlog.

    Now say you got the higher end of the range looking kinda good with
    the K's being close to 1.00 but the lower end still looks bad and the
    idle is a bit unstable.

    You can do several things in a situation like that :D

    Slide the breakpoint to the left
    Change the low slope
    Change the offsets that are at and around idle voltage
    Change the maf t curve points that are at and around idle

    Other idle considerations :)

    Have you done anything with your tb airflow scalar
    Have you done anything with your isc neutral idle airflow function

    Also ... Your mechanical adjustments like .............

    TB blade stop screw
    Bleed screw under that little rubber plug

    Those can hose up the idle if they are kinda far out of adjustment :bang:

    Have you got any stuff like breathers in place allowing unmetered air

    Have you looked at the seal around the pcv valve cause they can get
    brittle and leak around them causing an unstable idle as well

    Hope some of that helps :)
    If I was not all that clear on some of it ... just let me know ;)

  8. ^ Alright, you got me thinking about this some more. I am not going to do anything with the battery offset for now. I am going to look back over my log and see if I can't tweak the high/low slope a little. Looking through my avg kam is 0.95, which doesn't seem that far off from 1. 5% if I am calculating it right.

    But I am going to tweak my high/low a little then try to log over the next few days to get a better battery offset.

    I know I should have by now, but I have not gotten into that yet. :eek:

    My pcv should be good, it is sorta new and I don't have any un-metered air.

    edit: Just noticed I did not get the CEL today. :)
  9. I used this idea to tune the Battery Offsets:

    First before you start to mess with the slopes and MAF use both slopes equally , this will allow you to tune directly to the injectors without any other factor moving the data. Do a couple of runs using different accessories ( AC , Windshield Wipers, Headlights, etc) make EA work till you found your best Battery Offset, then start with the slopes, and finally do the MAF transfer work.

    But also first of all you should really dial your idle data (TB Flow) otherwise if you tune that in the end or in the middle you will be chasing your tail.

    It’s a really long work and it could be painful sometimes but in the end its worth to have a near stocker reliability.
  10. I certainly would not disagree with the above info

    I would like to point out one more thing

    But also first of all you should really dial your idle data (TB Flow) otherwise
    if you tune that in the end or in the middle you will be chasing your tail.

    If you do this first ... and I think it is wise to do so :nice:
    You make notes of K readings after these changes

    After working with your slopes ... You WILL see the K's change :Word:

    By that ... I mean the K values at and right around idle conditions


    Don't just focus on the word ... idle
    A low load cruise driving condition is the same as an idle condition

    I like to focus on the maf voltage values a good bit of the time

    Pulsewidth values can sometimes mislead you as well if the adaptive is
    hard at work and close to it's maximum limit.


    After getting the tb scalar and air flow function points all squared away ...
    I'd not change them

    I'd get as close as possible with the low slope
    and then
    See what can be done with slight tweecs to the idle t curve points

    Yes ... you can spend a good bit of time with the CL tune :crazy:
    These days ... So many have given good, reliable, info :nice:

    That info can R E A L L Y cut down the trial and error part of it :banana:

  11. another thing whose importance is often overlooked is the exhause pulse delay.

    if you have long tubes, or if for some other reason your O2s are farther away from the exhaust ports than stock, you should try to get those right early on, because otherwise, the feedback from the O2s back to the computer is out of sync with what the computer thinks, so the decisions it makes are not very accurate

    also, if your cam is very different from stock, the injector timing is important, because if the injectors start firing too late and the valve closes before the injectors finish firing, then the O2s will report lean, and the computer thinks it needs more fuel, so it fires the injectors more, but that doesn't help because the valves close before the fuel makes it in. then every so often enough fuel has pooled somewhere and it alot of it gets sucked down into the cylinder, causing a misfire and the car stumbles. and the gas mileage is terrible. i believe that is the situation i am in right now
  12. I think my o2 is in about the stock location. This is a turbo setup so I don't really know. It looks like it is near stock location after the turbo.

    Anyways I did more logging today with my new slopes. :rolleyes: It is still rich so I have to go from

    I need help with this right here. My hard start problem is still there.

    This is my log.

    That is my tune
  13. Don't know if you are talking low slope or high slope
    Many have used this rule of thumb to start out with slope values :)

    High slope value = inj size
    Low slope value = inj size X 1.2

    or in your case ........

    High at 42
    Low at 50.4

  14. raised my low and high slope but my kams went down :nonono:

    I was avg. .95, but now I am at .94 kam. My low slope has gone from 43.5 to 45.5 and high from 48 to 48.5

    Should I start using my offset now instead of the injector slopes? 45.5 seems high to me for a low slope. This is really just creeping along. Its not like I am near WOT.

    Most of the time my kam was below 1, even down into the .8xs. Only for about 10 seconds I went above 1. When that happened the only difference I see is that my load went above 40.

    Should I lower my low slope back down to 43.5 and just raise my high to 50 or so? I know that high slope is idle, but can also be light throttle. What is considered light throttle though?

    Sorry for all the questions, but I am :doh:
  15. Believe me ;)
    I understand ... It took me a while to catch on myself :Word:

    Your low slope effects idle and just off idle
    Very light load cruise

    High Slope will effect .........

    higher loads
    greater pulsewidth
    higher maf volt

    kinds of conditions

    Have you ever taken the time to read through all those EA help files :nice:

    Here is a thought that might help :shrug:

    Take a cruise with the tps position included in the payload

    Then you can see how the amount of open throttle relates to stuff like .....
    CL or OL
    injector pulsewidth
    maf volts
    yada yada yada

    It still seems like to me :shrug:

    You're trying to tune without a basic understanding of how :bang:
    the pcm sets up fuel and spark values
    based upon the input from the various sensors

    Maybe some of the other peeps can lay it out in a more clear way :nice:

  16. think I might have figured out my problem. About a month ago I messed with my battery offset. So I was thinking, maybe I need to change that back. I put it back to what I did have and put my high slope back on 43.5 and low on 49.7 (just a random number)

    Loaded my tune and drove with no logging. Came back 4 hours later and started doing some logging. Now my avg kamrf is 1.005787452 :) It was down to .94 and up to 1.04 but avg came out decent.

    EA said to lower my high slope just a tad so I am going to do that. Then I am going to work on my battery offset to try and get it near perfect and work on my idle. Hopefully I can get my wideband working too.

    edit: forgot I have to work on WOT
  17. I have been messing with this for a while. I am having better luck, but I guess it is going to take time. My newest logs show my avg ltft 1.05 and EA recommends me changing high slope from 43.6 to 41.6535 and my low stays at 49. It also recommended mine adjustments for my offset, so I will do that too.

    I got my wideband working so that should help too. I did notice that when I let off the gas the car is going lean again. Like 17 afr. The eectuning board is down, but I know I have seen something about lean tip in
  18. Going lean on coast is a-ok.

    Datalog your wideband in with the twEECer and you can see if you have any lean tip-in issues. Use scalar PID "AIR_MAN_VOL" to nix a tip-in lean/rich condition.

  19. after researching, I think I have lean decel not lean tip-in. The only thing I dislike about it is the car starts jerking, kinda like driving over bumps. This could be another problem though.

    When I calculate my offset EA tells me to move my 14.00 from 0.7500 to 0.8932. Does that mean it gets more fuel?

    Also, what would cause the car to get out of CL? I am driving around without giving it much throttle at all. Looking over my log, it shows go from CL to OL about every 3mins for 30 seconds or so. :shrug:

    BTW, when I did the offset for my wideband it did not work perfect. Like when I put 2volts for high/low in lmprogrammer, calcon was showing 19.79-19.84 (not 19.79) For the low it should different fluctuating numbers. I just added the two together and avg them out :) If I compare it to logworks it looks very close.
  20. Log the load and spark when you experience this. Try dropping the spark by 10 degrees and try it again.

    Correct, that will increase the injector pulsewidth and add more fuel.

    You got me on that one man.

    Sounds like you got some jitter. I have mine scaled as 10:1 = 1v 16:1 = 5v. Gives you a bit more resolution and will negate any sort of electrical noise you might be getting.