| Author | Message | ||
     Ferocity02 |
So a couple months ago I did a little "tuning" on my bike using VE Analyzer in MLV. I know this isn't the best way to tune, but I was hoping to smooth out some of the rough edges. I installed a narrowband O2 sensor in the front headpipe as well and have it all wired up to I can easily switch between the two sensors. I would tune one cylinder at a time. Overall, the high TPS values were leaned out, while the idle and cruise areas were richened. In total, the front cylinder was richened up by 280, and 614 for the rear. My gas mileage noticeably dropped about 5mpg. When I was tuning, I locked the AFV to 100. Once I was done I unlocked it and made a 90 minimum and 110 maximum. In a very short ride, the AFV dropped to 90, which leads me to believe that it did not like the richening up for the cruise area. So my question is, what do I do with the AFV after tuning. Obviously if the fuel maps richens up the AFV is going to try to correct this. Any ideas? Thanks! | ||
| Mr2shim |
Your AFV floating between 90-110 is pretty decent IMO. I've got mine to float between 95-105 but that was with months of Analyzing. I think(my opinion) You're not going to get your AFV to stay suck on 100% when unlocked no matter what you do. Different atmospheric temps, humidity, hella hot/cold days, all that mother nature crap. As long as it's within a decent range of 100% of the map, you're good to go. Or, if you're not satisfied you can just upload the stock map and start over. Re-reading your post, the variation between 90-110 in a very short ride (I assume sub 5 miles?) If I were you I'd just throw the ol' laptop in the backpack and go for another ride, or you could set your AFV to 900%, log that, see if VE analyzer would choose to richen up the map in the area it see's that it's running rich. (Message edited by mr2shim on October 19, 2008) | ||
| Moosestang |
If the AFV is at 90, is it leaning it out across the board or only in the Closed loop box? While on the subject of the closed loop box, has anyone moved the box around the map? Mine covers quite a large number of cells and i've seen others that are much smaller. What would making it smaller accomplish, besides the obvious fact it will add or subtract fuel from fewer cells. | ||
| Ferocity02 |
The AFV I believe is only applied to open loop operation, which occurs when the engine is cold and at WOT. My thinking is that if the AFV dropped to 90 on a short ride, this is probably indicative that it wants to go down even further. I set the minimum to 90 for this exact reason, I didn't want it leaning out the fuel too much. Basically, it seems like the ECM will automatically try to get the AFR to it's specified value by means of the AFV. Which in my mind makes tuning useless because the AFV is going to mess it all up anyways. The only way I can see to remedy this is to somehow adjust what the AFV is trying to accomplish. | ||
| Moosestang |
The AFV I believe is only applied to open loop operation, which occurs when the engine is cold and at WOT. I think you may have that backwards, but i'm no expert on ecmspy. The AFV doesn't even start to change until the bike goes into closed loop | ||
| Froggy |
Ok no expert either, but I also thought AFV comes into effect during closed loop. For example, by bike was hating Georgia during Buelltoberfest. Running under 4k RPM would make it run like crap because the AFV was in the 60s. Over 4k it was 95% fine. Reset AFV to 100, after a few minutes in the twistys I could feel the AFV drop again. | ||
| Moosestang |
The AFV changes that fast? I thought it was more like long term fuel trim and ego correction was short term fuel trim? Those are automotive ecm terms. | ||
| Buford |
Made my maps using front and rear wideband sensors. Run it in open loop..very happy Buell.. | ||
| Froggy |
Want to know how fast it was? I did it again at the dragon. At the north end of it, pulled off at the big lot, reset the AFV, made another run south on the dragon. I don't even think I made it half way without it getting severely skewed. I stopped at Deals Gap, and the bike almost wouldn't start again. I didn't bother to reset it again, as it was a pain in the ass to undo my luggage. It smoothed back out as I was riding gently after. | ||
| M1combat |
Tune the closed loop area to 14:1 AFR. Tune the rest as you see fit. | ||
| Ferocity02 |
Here is how the ECM calculates how much fuel to dump in... Open loop = fuel table * AFV * Tab_CR_TE (WUE) * Tab_CR_AT * KCR_Open_Loop Closed loop (including Closed Loop Learn) = fuel table * Tab_CR_TE (WUE) * Tab_CR_AT * EGO_Corr Open Loop WOT = fuel table * AFV * Tab_CR_TE (WUE) * Tab_CR_AT * KCR_WOT Where: Tab_CR_TE (WUE) is the correction for engine temperature Tab_CR_AT is the correction for inlet (airbox) air temperature AFV is the global correction to the fuel table to take into account other uncertainties not addressed by the above. The value for this is generated in the Closed Loop Learn region only. EGO_Corr is the instantaneous correction for closed loop control KCR_Open_Loop is the factor applied to the fuel table when in Open Loop KCR_WOT is the factor applied to the fuel table when in Open Loop WOT | ||
| Xl_cheese |
I had the exact same results as you tuning with front and rear o2 sensors. Your assumptions are the same as mine in that making CL richer the AFV will drop to compensate. Thus leaning out the OL area which is worse because MLV leaned it out too. I gave up on it. I have read about people using wideband o2's and not getting good results either. I was able to tune the idle well with the dual o2s... That's pretty much it. | ||
| Firemanjim |
Guys, the LCL area in your ecm shown on ECM SPY is where your ecm learns from the O2 sensor and applies these changes globally to entire map. If you richen in the "learn" areas it will affect EVERYTHING!!!Tune this area to 14.7, you can richen up other areas as you see fit. Idle likes a bit more, and WOT. Your O2 sensor and FI are designed to work in the 14.7-15.1 range . | ||
| Id073897 |
If you richen in the "learn" areas it will affect EVERYTHING!!! Will affect open loop only. Regards, Gunter | ||
| Xl_cheese |
We are tuning to 14.7:1. MLV is calculating a richer value. I don't think the MLV model works very well. Gunter is correct. CL bike uses EGO.corr. which uses o2 sensor. OL - AFV | ||
| Swordsman |
I still fail to understand why we even need Open Loop and AFV? Seems like Buell went to an awful lot of trouble to circumnavigate a fairly straightforward idea: calculate off the available oxygen. If you had a correct oxygen reading at all times, why would you ever need all this other stuff? ~SM | ||
| Id073897 |
I don't think the MLV model works very well. The MLV model works perfectly well, as proven in thousands of MegaSquirt installations. Regards, Gunter | ||
| Firemanjim |
Can you give me a short explanation of the EGO? What it is,does, how you are using it? Thanks,still learning this stuff. Gunter, I stand corrected but you know what I meant. | ||
| Xl_cheese |
The MLV model works perfectly well, as proven in thousands of MegaSquirt installations. Then why does it give poor results for our Buells? | ||
| Xl_cheese |
Can you give me a short explanation of the EGO? What it is,does, how you are using it? Thanks,still learning this stuff. Open up ecmspy and watch it on the ecm runtime tab. You can also watch it on a Datalog play back. Graph ego corr right on top of the O2 data in MLV. | ||
| Gemini |
close but not all the way there. in open loop, the bike will use the current value of afv. in closed loop, it still uses afv but will also use ego. a comment was made earlier the the auto terms are long term and short term adaptive. that is correct. buell just uses differant terms for the same thing. in closed loop. it will take afv in a percitage and add it to ego in a percentage. the total percintage will be applied to the numerical value of the cell that it is in. ex, afv is 110. ego for that split second is 105. the value of the cell is 54. 1.1(afV) X 1.05(EGO) X 54=62.1 this the value that is used for fuel injector pulsewith. i don't know what the multiplier of fuel in milliseconds is, but 62.1 x 8 milliseconds(i think this value is right) is what is actually happening. in open loop. afv still at 110 and still using cell value of 54(keeps things consistant. something a little differnt happens. insted of using ego, it will use the open loop default. in this case we will say it is 110. 1.1(afv) x 1.1(open loop default) x 54 = 64.8 for that cell in open loop. If you richen in the "learn" areas it will affect EVERYTHING!!! Will affect open loop only. Regards, Gunter this is right and wrong. if you tune your closed loop learn area to the wrong fuel ratio, the next time you drive the bike in normal operational mode, you are going to see you afv shift to bring your fuel ratio in closed loop learn back to 14.7. because the afv will change, the whole fuel map is shifted the same amount. afv is only changed by drving in closed loop learn area or by ecmspy(or other tool). while this is not harmful to the bike in closed loop mode because the afv and ego work together to keep the bike at 14.7, it may have very unwanted results in open loop. again, another crude example. you tune your bike to 13.2 in closed loop learn area. when you run the bike in normal mode in closed loop learn, it will lean the bike back to 14.7. for example sake, it takes the afv down to 85%. bike is happy in closed loop. you go back into open loop mode with the same numbers we used before. .80 (afv) x 110 (open loop default) x 54. =48.6 this is not only going to be a loss of power, but depending on how lean it is, can cause damage. and because the bike is in open loop, it doens't know it is running lean. i hope this explains some of it in a little more detail. i am always open to more questions and to "debate" different opinions. i will not accept any rude or offenseive comments. to say "NO, you are wrong", i will ignore. you bring to the table "hey, how about this....", i'll listen all day. | ||
| Xl_cheese |
gemini, Are the above equations posted by Ferocity wrong? Your explaintion states that AFV is also a variable for CL? Open loop = fuel table * AFV * Tab_CR_TE (WUE) * Tab_CR_AT * KCR_Open_Loop Closed loop (including Closed Loop Learn) = fuel table * Tab_CR_TE (WUE) * Tab_CR_AT * EGO_Corr Open Loop WOT = fuel table * AFV * Tab_CR_TE (WUE) * Tab_CR_AT * KCR_WOT (Message edited by xl_cheese on October 22, 2008) | ||
| Gemini |
i am curios what "Tab_CR_TE (WUE)" is? | ||
| Skully |
First, I want to thank Gunter for the awesome job he did writing this software an then providing it free of charge! I own both VDSTS and DirectLink. ECM Spy does much more. Second, assuming (ahem) the bike is in good running condition with no major fueling issues, it would seem that when data logging, you would want to disconnect the O2 sensor, yes? Otherwise, the closed loop section will be updating while you are riding. Third, assuming (ahem) that you do want to disconnect the O2 sensor, is it possible to do this using ECM Spy? Someone mentioned "locking" the AFV. Thanks, Keith | ||
| Xl_cheese |
i am curios what "Tab_CR_TE (WUE)" is? Check up a few posts at ferocity's original one. He explains what each variable is. | ||
| Gemini |
skully, lock the min and max afv to 100. keep the o2 sensor pluged in or you can't watch the o2 levels for tuning. i leave the afv range normal. megalogviewer is supposed to take into consideration the changes in afv and ego when plotted out changes to your fuel map based on the datalog | ||
| Gemini |
i am curios what "Tab_CR_TE (WUE)" is? Check up a few posts at ferocity's original one. He explains what each variable is. so obviously in front of me i couldn't even see it. lol the only thing that i know that is missing in the closed loop one is that afv is also applied. | ||
| Typeone |
i leave the afv range normal. megalogviewer is supposed to take into consideration the changes in afv and ego when plotted out changes to your fuel map based on the datalog i leave the AFV range normal as well. that reminds me... FYI, Gunter has updated the Bin2Msl converter as of last week... I put a now binary-to-msl convertor on the server: http://www.ecmspy.com/download/Bin2Msl.zip Changes: better recognition of accel/decel states (variables "Accel Corr." and "Decel Corr.") and writing the engine byte now, which is used internally by the MLV software. Please update! Regards, Gunter Thank you, Gunter!  | ||
| Gemini |
is that for the pc version of ecmspy or for the palm only? | ||
| Typeone |
Gemini, its a PC Java app. i log in binary on the Palm, copy log.bin to my PC, run it through the Bin2Msl then open in MLV for analysis. |
