| Author | Message | ||
     Kpg2713 |
Alright, I got an '06 scg w/ 1500 miles on it. I've had the tps reset a coupe times, adjusted the idle, re-adjusted the idle, and have ridden it to get the computer to lean all this crap. So it runs decent sometimes, other times it falls flat on it face leaving lights. Some days it feels great, others it has no grunt and seems like it is definately down on power. Anyway anyone can give me a little more insight? | ||
| Spatten1 |
Did you do a steady state ride at about 3k rpm for 3-5 minutes? Sounds dumb, but sometimes that is all that will straighten out the ECM, expecially after a big change in ambient temp or altitude. | ||
| Captain_nartman |
^ what Spatten1 said. N x | ||
| Tpoppa |
Could this be a stator or voltage regulator issue? | ||
| Kowpow225 |
Very possible. Mine felt a little 'dead' when I had a charging problem. (loose connector behind front sprocket cover) | ||
| Kpg2713 |
Didn't realize I was suppose to ride it steady for a few minutes at 3k. I usually ride at about 4k so Ill do that. I don't think I have a charging problem. Thanks guys. | ||
| Saintly |
Here's a related question. Does anybody know if having the battery disconnected for long periods of time(4-5 days) will cause the XB's ecm to "lose" the adaptives that it has "learned"? I have a similar situation with my 07' 9R. Sometimes it feels ok, other times is pops and farts and just runs horribly. It's a complete and total slug when I really get on it. (I took my 03' out for a comparison ride a few days ago, just to be sure that I wasn't imagining it). I've had the TPS reset already and that helped for about 500 miles but it gradually got bad again. I ask about the battery disconnect because after I re-connect the battery, the bike feels much better for about 2 or 3 hours then returns to crap mode. I also notice that after re-connecting the battery, that my idle setting is always different. For example: if the bike is idling at 1000 rpm for a week straight and then I disconnect the battery, when I re-connect it a few days later and fire the bike up, it will now idle at 1250 RPM. So I lower the idle adjustment, but next time it will be different again. Any input? | ||
| Firebolteric_ma |
I am only guessing here but it may have to do with your A/F values and the way the ECM changes the Fuel tables in the stock mapping. The A/F may reset when disconnnecting the battery? I don't really think so but maybe? Try resetting the A/F with the VDSTS. See how that works out. Does it happen more with big elevation changes? Mine acted up pretty badly when I was at Bear MT once and the weather was foggy/rainy. My A/F was way off. Threw my whole map out and I had to reset it w/ Direct link whan I got back to run well again. | ||
| Buellshyter |
This whole notion of riding around at 3500 rpm for 5 minutes is one of the dumbest things I've ever heard of. Yea, I believe it's what needs to be done but why in the world would someone even design something like that in the first place. I don't need to do that with my cars to get them to run correctly !!! It's 2007 for Pete's sake | ||
| Davo |
Kpg, I ran into a xb9 that was having problems and the dealer and a local bike shop looked at it. No codes but the plugs were rich. They both told the owner to just ride it. I drained the fuel tank and found a small amount of water in the tank and that fixed it. It was only a couple of thimbles full of water. It was an easy fix. Ran like a different bike. I would also check the timing if there are no codes and the fuel is OK. (Message edited by davo on April 26, 2007) | ||
| Brewtus |
This whole notion of riding around at 3500 rpm for 5 minutes is one of the dumbest things I've ever heard of. Yea, I believe it's what needs to be done but why in the world would someone even design something like that in the first place. I don't need to do that with my cars to get them to run correctly !!! It's 2007 for Pete's sake Hey Buellshyter, Cars now days learn the same way. LTFT or long term fuel trim is the same thing in a modern car as far as I understand. If fuel trim is reading high it means that the vehicle is trying to add fuel for some reason. ( plugged fuel filter, air leak in intake system, ect.) If the fuel trim is negative the vehicle is trying to remove fuel ( opened EGR valve ECT.) You problably don't notice much on you're daily drive in your car because modern cars are MUCH more advanced than bike EFI. | ||
| Spatten1 |
This whole notion of riding around at 3500 rpm for 5 minutes is one of the dumbest things I've ever heard of. Yea, I believe it's what needs to be done but why in the world would someone even design something like that in the first place. I don't need to do that with my cars to get them to run correctly !!! It's 2007 for Pete's sake Yep. Brewtus, my understanding is that cars learn with more sophisticated algorithms and actually have enough sensors to make quick changes for the changing environment. They have much more rigorous emissions testing requirements and have to perform differently than motorcycles. The Buell system is very "sensor light" and uses calculation and a quick processor to make up for it in closed loop. It seems that the Buell guys' primary focus in 2002 was to meet 2008 emissions requirements. The system has a really fast processor and works really well in closed loop, thus the high fuel mileage. However, it is just stupid not to have a MAP or atmospheric sensor to make quick changes to the open loop curves. Typical open loop systems function better than our closed/open loop system when it comes to adjusting to changing conditions. I'm the first to say this system works great in closed loop. However, it really takes a crap sometimes in open loop, and I think an extra sensor or two would be all that is necessary to update it for better adaptability. Last time I posted this opinion, about two years ago, the reply from a huge poster here was STFU, and I didn't even know what that meant! | ||
| Tx05xb12s |
Can you shed some light on what open and closed loop means? | ||
| Davo |
Closed loop is when the ECM is constantly making changes to the fueling based on the O2 sensor monitoring the exhaust. Open loop is when the fueling is based on predetermined fuel maps The Buell system, VDO-EFI, uses both modes. The closed loop system works during basic cruise mode and the open loop system is used during low speed and high speed. The Buell system's open loop system is not completely open (unaware of external changes) because during closed loop the system makes adjustments to achieve a 14.7 to 1 AFR and the system makes changes to a factor called the AFV (adaptive fuel value) which compensates for significant changes in closed loop operation and alters the open loop map. For example if the engine is running richer than normal in closed loop and you nail the throttle then the open loop mode is made leaner than it would have been required during the factory set open loop fuel map. (Message edited by davo on April 27, 2007) | ||
| Tx05xb12s |
Thanks. So, by running at a constant 3,000 RPM, you're using the closed loop to train the AFR & AFV, which in turn calibrates open loop operation at high RPMs for better performance. Is there any literature available about our engines? I'd like to learn more. | ||
| Brewtus |
Hey Spatten, I agree. If they would use a MAP of MAF sensor I think our bikes would run way better. | ||
| 07xb12scg |
I have the same problem Kpg. It's my biggest complaint with my Buell! | ||
| Spatten1 |
Brewtus, my best guess is that they had trouble with the MAP due to the twin's intake pulses, and a MAF is just too expensive. Still, a MAP outside of the airbox (which would actually be a AP)... would give the corrective info needed for altitude adjustments. I also think there must be some way to baffle a MAP so it would give effective info. | ||
| Spatten1 |
KPG AND 07xb12scg: Please let us know what happens after a 3k steady state run. | ||
| Hkwan |
Yea, let us know what's up... | ||
| Firebolteric_ma |
This should answer your questions on how the buell system works. Dynamic Digital Fuel Injection The Basics of Buell's Electronic Fuel Injection System Buell's Dynamic Digital Fuel Injection (DDFI) enhances engine performance using advanced computer technology. A microprocessor inside the Electronic Control Module (ECM) makes hundreds of changes per second. Each adjustment allows precise fuel and ignition mapping to the Buell powerplant for the current environmental conditions. The speed that the system can change the fuel & spark delivery to the Buell powerplant is incredible. The Buell DDFI can make hundreds of changes per second. Benefits of this system include an improvement in midrange power, easy cold starts and onboard diagnostic capability. This system also compensates for altitude changes. The DDFI system uses several sensors to provide feedback about external and internal operating conditions to the electronic "brain" of the system, or ECM. These conditions include: Rider input (throttle position) Engine load External environmental conditions (outside air temperature) Internal engine environment (cylinder head temperature) Each of these conditions must be known in addition to the information already "memorized" by the ECM. This is necessary for the ECM to perform the calculations necessary to deliver the optimum spark advance and fuel amount for each engine cycle for maximum performance as well as to meet government regulations for emissions. The method of how the required amount of fuel for any combustion cycle is calculated depends on the type of the EFI system. The three types of EFI systems are open loop, closed loop and combination open/closed loop systems. The first type of EFI system operates as an OPEN LOOP system. The ECM calculates and delivers spark and fuel based on a set of predetermined spark and fuel "maps." These "maps" provide the base information necessary to run the engine with only minor adjustments for external/internal environmental conditions. This method is accurate to the degree that the "maps" are accurate. The Harley-Davidson systems are open loop. The second type of EFI system operates as a CLOSED LOOP system. This system not only uses spark and fuel "maps" but also feedback from an exhaust gas oxygen (O2) sensor to continually adjust the amount of fuel delivered. This offers the advantage of "learning" the behavior of the engine over time as well as responding to a wider variety of conditions encountered while riding than that of an OPEN LOOP system. The Buell DDFI operates both as an OPEN and CLOSED LOOP system. This is necessary to adjust for all possible operating conditions. Buell's selection of high lift cams (which enhance engine performance) make it necessary for an open loop system at idle and wide-open throttle. Furthermore, when operating in open loop during cold start and idle, the system will utilize programmed fuel and spark maps in the ECM for ease of cold starting and to provide a stable idle. When the bike is at a steady cruising speed and operated under a light load, the DDFI system switches to closed loop operation. The system then continuously "tunes" the performance of the engine to compensate for changing conditions and provide maximum performance by using the O2 sensors input. General operating parameters for open and closed loop running. Return to Menu OPEN LOOP Idle and starting slow speeds under 20mph (1500 rpm) High speeds above 60mph (4,000 rpm) accelerating from low speed accelerating from high speed decelerating CLOSED LOOP Cruising between 40 - 60 mph at operating temp. (1500 to 3500 rpm) How does the Buell DDFI system work? Return to Menu The ECM uses six different sensors to monitor rider demands and changing engine conditions to determine the correct fuel and spark requirements. These sensors are: Throttle Position (TP) Sensor Cam Position (CMP) Sensor Intake Air Temperature (IAT) Sensor Engine Temperature (ET) Sensor Oxygen (O2) Sensor Bank Angle Sensor (BAS) The ECM needs the information from the TP and CMP sensors to calculate how much air is entering the engine. The TP sensor is attached to the throttle shaft on the left side of the throttle body. The CMP sensor is located in the gearcase cover on the right side of the engine. The TP monitors the amount of air entering the engine, by how far the throttle is open, whether it is opening or closing and how fast it is opening or closing. The ET Sensor provides the ECM the current engine temperature. Proper fuel and spark delivery are dependent on the temperature of the engine. The ECM will provide a richer fuel mixture on start up and a higher degree of spark advance. As the vehicle warms up to operating temperature the fuel mixture will lean and spark advance will decrease. The IAT sensor, mounted in the Helmholz Volume Power System (HVPS) air box, measures the temperature of the air entering the engine, when combined with the TP and CMP data the ECM can determine the density of the air entering the engine. The ECM also monitors the CMP sensor to determine the exact position of both cylinders in the combustion cycle and the engine speed. The fifth sensor is the Oxygen Sensor (02). It is desirable to operate the engine at or near stoichiometric, or approximately 14.6 parts air to one part fuel. The inclusion of the 02 sensor allows the ECM to ensure a proper air/fuel mixture is delivered to the engine by monitoring the final combustion efficiency in the exhaust system. This ensures optimum engine performance at any altitude. The sixth input is the Bank Angle Sensor (BAS). This sensor provides the input to the ECM that the vehicle is not leaning greater than a 55 degree lean angle. If the vehicle exceeds a 55 degree lean angle the BAS will interrupt the operation of the ignition system and the fuel supply. How does the O2 sensor measure the fuel mixture? Return to Menu An Oxygen sensor is a chemical generator. It is constantly making a comparison between the Oxygen inside the exhaust system and air outside the engine. A Zirconium stabilized yttrium oxide ceramic shell is coated with a layer of platinum. When the nose is heated the platinum will begin to react with the exhaust gasses and a voltage potential will form between the inner and outer layers. The sensor does not begin to generate it's full output until it reaches about 600 degrees F. Prior to this time the sensor is not conductive. This voltage output of the sensor is usually between 0 and 1.1 volts. A rich mixture leave very little free oxygen and the reaction will send out a voltage greater than 0.45 volts. If the engine is running lean, all fuel is burned, and the extra oxygen leaves the cylinder and flows into the exhaust. In this case, the sensor voltage goes lower than 0.45 volts. Usually the output range seen seen is 0.2 to 0.7 volts. The mid point is about 0.45 volts. This is neither rich nor lean. A fully warm O2 sensor will not spend any time at 0.45 volts. The O2 sensor is constantly in a state of transition between high and low voltage. Manufacturers call this crossing of the 0.45 volt mark O2 cross counts. The higher the number of O2 cross counts, the better the sensor and other parts of the computer control system are working. It is important to remember that the O2 sensor is comparing the amount of oxygen inside and outside the engine. If the outside of the sensor should become blocked, or coated with oil, this comparison is not possible. Also if the exhaust side of the sensor has been contaminated by using leaded fuels or gasket sealers which are not specifically identified as being approved for use with oxygen sensors the sensor can be permanently damaged. ADAPTIVE FUEL VALUE Return to Menu The Buell DDFI system has the ability to “learn” the engine fuel mixture needs. When the motorcycle is running in the closed loop mode and operated in a specific engine speed and load range, the system will compare the feedback from the O2 sensor to the base programming stored in the ECM. If a difference in these values is detected, the ECM will recalibrate the system program to compensate. This correction is termed the adaptive fuel value or AFV. This compensation value allows the system to adjust to different altitudes, air densities, and to some degree engine variations and wear. The normal AFV ranges based on altitude are between 85 and 115. The higher values are found at lower altitudes and the lower values at higher altitudes. The AFV correction is only applied to the fuel mixture during OPEN loop operation. During closed loop operation the O2 sensor signal is the primary compensation method. The AFV will be learned when the bike is operated at engine speeds between 2500 and 3500 rpm at road speeds in the 40 to 60 mph range under a steady light load (no down grades or steep upgrades, decelerating or accelerating) for 2 to 3 minutes. The AFV can also be reset to 100 by using the scanalizer at any time. The AFV value can be a valuable diagnostic tool. Compare the AFV values of bikes in your area which are running fine during routine services. When you are working on a bike which may have a DDFI problem, compare the values. If the AFV is higher than normal, the system is trying to correct for a situation which is causing the mixture to be too lean. Look for intake manifold or injector O-ring air leaks, incorrect ignition timing and TPS zero setting, low fuel pressure or a fuel line restriction as well as a sensor malfunction. If the AFV is lower than normal, the system is trying to correct for a situation which is causing the mixture to be too rich. Look for incorrect ignition timing and TPS zero setting, high fuel pressure or a leaking injector as well as a sensor malfunction. The O2 sensor can also cause the AFV to be set incorrectly. Internal shorts in the lead, poor electrical contact with the exhaust system or contamination can all affect sensor performance. O2 SENSORS CAN BE CONTAMINATED BY SILICONE SEALERS!!! ONLY USE SEALERS WHICH ARE LABELED O2 SENSOR SAFE IN ANY LOCATION WERE THE VAPORS CAN COME IN CONTACT WITH THE SENSOR. (top end of engine) | ||
| Tx05xb12s |
Thanks Eric. That was cool of you to post all that information. What was the source? | ||
| Kpg2713 |
Wow, that explains a lot. I need to go out and run the bike so it learns the AFV tomorrow. I believe this may help. I never ride it steady 40-60 mph at 2500 to 3500 rpms. | ||
| Spatten1 |
Kpg2713: Got any feedback for us? | ||
| Xl1200r |
Just as a note, I noticed that my bike was running like ass - lots of hesitation off idle, poor idle and would stall out sitting at lights once in a while. The hesitiation went away as the bike warmed up, but the stall outs would happen ice cold or piping hot. I just got the bike and installed a Spec Ops muffler just about right away, so I'm sure it's running all retarded. Last night I took it for a rip on the freeway at about 4200rpm for 5 minutes (I thought I read it needed to be 4000rpm, not 3000 - my bad). After that there was probably another 5 minutes or so running at 3500rpm. My house is right off the offramp, so I couldn't judge too much, but when I got home it seemed to be idling much better than before. | ||
| Spatten1 |
I think anything over 4000 rpm is open loop and will not help the ECM learn. The 3500 run may have done the trick. Try 3000 too. Please keep us posted as you continue to ride so we know if it works. It helped me when my bike was running like ass |
