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Thread: surging idle, high AFV

  1. #11
    damn how are you going to "bike" tease me like that?

    Personal computer not connecter to NPPRNET? lol

  2. #12
    Senior Member
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    Ever figure out what was going on here? my bike is doing something similar. it surges when cold though and then once warm the idle only drops every once in a while.

  3. #13
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    Lol ^^^^^^^ that **** is funny you really made me laugh Negative
    Shiiiiiaaat I wasn't laughing !! ... (I am now tho lol ...) ... It was probably one of my longest ECM operation explanations ever .... with spinning rims, pictures, chocolate cake and everything man ...

    damn how are you going to "bike" tease me like that?

    Personal computer not connecter to NPPRNET? lol
    Lol trust me it wasn't on purpose ... I poured a little of my heart and soul into that explanation ... it was .... glorious ... lol ...

    Yes these computers are connected to the NIPRnet ... but the LAN and the routers we use are terrible about losing and regaining connection suddenly which screws up a lot of the work you'll be doing on a webpage ... be it ADLS, vMPF, vPCGR, or the even the AF Portal itself ... anything ... and you can't put a personal computer on our LAN under any circumstances, it WILL brick it I promise you (and yes they do warn you ... often ... so it'll be all your fault) ... or memory sticks ... or external harddrives ... or plug your phone into the computer even if it's off just to charge it ... and trust me they know the minute you do it, I've seen the phone ring about 30 seconds after somebody plugged in an iphone one time to charge into one of the squadron's computers ... Our wing headquarters helpdesk don't play son ... lol I'm amazed this forum even makes it past the ridiculously stringent filters they have for stuff ...

    Let me start retyping this again ... it took me all of about an hour to type it up last time ... I'm getting into the habit of highlighting all my text and CTRL+C'n it before I post ... just in case it fails to post and I have to redo it again ... just like I did with this very post .....

  4. #14
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    Ok .... CTRL+C warmed up? ... check .... cracked knuckles twice? .... check check ..... deep breath ..... aaaaaaand go ....

    Before I post ANYTHING ... please let me be clear on one point ... I'm not sure how much of the operation of these ECM's you already understand so please don't take anything I explain that you already know as an offense to your intelligence ... I'm just starting from the beginning ...

    A quick explanation on the O2 sensor, the AFV and the EGO correction's influence on the fuel maps before we continue ...

    The O2 sensors first ... When most people think of O2 sensors they think of the wideband O2 sensors in a vehicle which put out a (more or less) steady voltage compared to our narrowband (otherwise known as lambda sensors) in our bikes ... which function basically as an on/off switch to the ECM providing a 1 or a 0 input for it to record and observe ... basically what the ECM looks for from it's O2 sensor when it's in closed loop and actually taking it into account is how many times it crosses the midpoint value it has stored over a given period of runtime ... in a perfect world it should be seeing 1, 0, 1, 0, 1, 0, 1, 0 or something of that effect ... we will see this as the EGO voltage fluctuating rapidly from a "high" voltage to a "low voltage (we're only dealing with 1 volt here) ... the more times it crosses over in a given time, the better ... now if you start running really rich or really lean the O2 sensor will start running at a consistent high or low voltage and putting out more 0's or 1's in a given time ... instead of 1, 0, 1, 0, 1, 0, 1, 0 it'll see 1, 1, 1, 1, 1, 0, 1, 0, 1, 1 ... this will mean you're running very rich and the computer will start taking fuel out to try and get back to a steady 1, 0, 1, 0, 1, 0 flow ... But remember, narrowband sensors are nowhere near as accurate as widebands are ... basically the ECM is putting for a "slightly more than educated guess" at what it needs to do to correct the fueling ... a lot of people make the mistake of changing parts or throwing in maps and thinking the O2 will make up the difference ... well only to a certain extent ... In a perfect world, the ECM's entire fuel map should be tuned for roughly stoichiometric running ... the O2 sensor is built in to compensate for day to day changes ... not correct wild fueling errors ...

    Which brings you to the EGO correction ... this is a percentage that your ECM gets from observing the O2 sensor's output when you're operating in a closed loop area of the fuel map and seeing if your engine is running consistently lean or rich... this percentage is applied directly to the fuel cell your bike is currently running in ... if it's a high percentage it's adding fuel, if it's low vice/versa ...

    Now ... The AFV .... Just like I explained above what EGO correction does to a certain fuel cell, the AFV does it to the entire map ... if your AFV is 110, it's applying 110% of the fuel to any given fuel cell in the fuel map no matter where your bike is operating at in the fuel map ... your bike gets the AFV by taking an average of how lean or rich the bike is running in closed loop from the EGO correction ... if you go out and run a log with your bike, you'll consistently see the AFV mimic the EGO correction percentage ... As explained before this is to try and get the fuel maps to run as perfect as possible so there's as little correction being applied from the O2 sensor as possible ...

    Now ... if you slap a map in your bike that's not tuned correctly for your modifications you'll have lean conditions and rich conditions in different portions of the map .... say your idle is good, but your cruising RPM's in the closed loop area are really lean ... when you first start up the bike after you put the maps in, it'll run great for a bit until you take it out on the road and cruise around in an area of the fuel map that's lean ... when your bike sees it's starting to run lean from the O2 sensor, it'll up the AFV to match what the O2 sensor is seeing (which applies it to the entire map as a whole) ... this will make that one particular area run great, but the rest of the map will run like **** ... when you stop at a red light and let the bike drop to idle the AFV will still be in effect to the fuel cell values in the idle portion of the map, but since it's adding fuel from seeing the previously lean readings from the O2 sensor your idle will be running crazy rich ... the O2 sensor will be trying to compensate and apply the EGO correction to the fueling, but it's also applying this to the AFV that the ECM has in place for the whole map ... so your fueling will just get worse ... narrowband O2 sensors aren't terribly accurate, they just kinda shoot for an average ... so the further the error it's reading the worse of a "guess" from the ECM it will be ...

    For the first picture ...

    Your engine is idling and at operating temperature so the EGO correction should be reading 100% in a perfect world during this sort of operation (or as close to it as possible in real world operation because of outside factors ... temp, humidity, altitude, etc.) ... in that picture I see it at 134% ... this is telling me your idle cell fuel values are reading terribly lean on the O2 sensor and it's taking the cell value you're idling in and adding 34% on top of what's already there ... also your AFV is showing 128 which tells me the cruising RPM's (about 2.5k-4kish) are also lean ... the AFV is a percentage that the ECM applies to the entire map as a whole ... so it's taking your entire map and adding an additional 28% on top of everything that's already there ...


    ----------------------------------------- To be continued when I get home from work .. ------------------------------------

  5. #15
    Senior Member rchuff's Avatar
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    Good job negative on the money baby!

  6. #16
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    Ok ..... so now that I have a fresh laptop, my router/modem decides to take a crap on me ... (gotta love suddenlink) ...

    Anyway ... on to the second picture ...

    The EGO value you've mentioned on there in the lower left portion of the screen is the EGO voltage ... so you'll see that number rapidly fluctuating just like you mentioned ... which is good actually ... you want to see it going from low to high quickly, the more times it crosses over the midpoint value for the ECM to see/record the better (that is known as hysteresis btw) ... if it's stuck either on the low or the high side of the midpoint voltage you'll see some error codes popping up and your ECM will lock itself into open loop mode ... (mine did this to me shortly after I got it running from a bad O2 sensor) ...

    On to the 4th and 5th pictures ... (the front and rear fuel maps) ...

    See those four little highlighted squares where the crosshair is located? ... those four squares are what the ECM is pulling from right then and there to run the engine ... the crosshair is exactly where you are on the X/Y axis in the fuel map ... So you should take whatever the EGO correction is showing for those four cells while your bike is running at operating temp just like it is in those pictures, kill your engine, highlight those four squares with your mouse, put that correction percentage into the little box just to the left of the Up/Down arrows (if it shows 134% like yours was in the first picture you'll be putting 1.34 into that box ... it multiplies the current values in the box by 1.34 and applies the changes), and hit the little asterisk button right to the left of that to put those changes on the map ... then you can turn the key back on, connect your ECMspy, burn the map with the updated idle values, turn the key off, then back on, restart the bike, and check the EGO correction value again ... see if this has made an improvement ....

    Basically what you're doing right here is using the O2 sensor to help you tune the maps ... since you have a DDFI 2 bike with an idle screw, you can adjust the idle screw further up along the RPM range to do the same with other cells in the closed loop areas as well ...

    For the ignition map pictures ... I recommend not messing with those unless you have access to a dyno and someone who knows how to use a dyno to put a load on the bike and adjust the timing ... timing is a little touchier than fueling and it's easy to lose power very quickly with only small adjustments ...

    For the 7th picture ... your "Other Maps" page looks pretty much like stock settings to me, which is just fine for street riding ... I recommend not messing with anything on there ...

    As for the last two pictures from after you shut the bike down and reset the AFV ... you mentioned the TPS value jumping a little between two numbers on there ... that's happened to me as well with ECMspy hooked up to my bike ... whoever wrote the ECMspy program designed it to translate the voltage values into other, easier to understand values for us to read (The ECM sees nothing but voltage inputs from it's sensors, the program changes those to percentages, temperatures, RPM's, and other values) ... if your sensor is showing a voltage that translates directly in between two percentage reportable values, the program will get stuck in a loop trying to show both at the same time .... if it's only a very small percentage (such at the 0.9% discrepancy that you mentioned) you shouldn't have a problem with the TPS on your bike ... if you're seeing it jump from 5.2%-70% or something like that, then yes you have a faulty TPS...

    You can test the function of a TPS with ECMspy by slowly opening and closing the throttle while watching the output voltage or percentage and making sure you see a steady rise/fall correlating with you moving the throttle ... if you see any peaks/dips ... you need a new TPS ...




    WHEW !!! ... ok ... I think that about covers it ... as far as reviewing your post ... clear as mud? ... questions ? ... feel free to ask away and I'll help to the utmost of my ability ...



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