| Author | Message | ||
     Unlucky1 |
Howdy folks. I am new here, bought a 2006 Ulysses earlier this year and am trying to sort it out for summer touring. I live at sea level and we typically see a lot of altitude change on trips (last summer we rode Teton Pass at about 8500 feet). Seems like there is a lot of knowledge here after reading through some archives, so I have a brain dump based on what I've read about the ECM (ecmspy manual, forum searches, etc), was wondering if somebody could correct my misconceptions or whatever. Also, I have some questions. Background: Right now it is set up by a previous owner with a Jardine can, a remapped ECM by a local dyno guy (http://2wheeldynoworks.wordpress.com/), an OEM disposable air filter, and the O2 sensor is disconnected. The guy I bought it from says the O2 is disconnected so that the ECM doesn't reset to EPA lean. It currently runs... pretty rich; I can smell gas when I start it, it doesn't get nearly as warm as my friend's '07 Uly running a K&N, Drummer, and EBR Preprogrammed ECM, it gets less fuel economy than I think it should - just over 30mpg, and it takes forever to warm up. It also throws a code about the O2 sensor every time it wants learn mode. I have a K&N on the way and looking at the American Sport Bike receipts I can confidently assume it was tuned with the K&N on it, so I assume that will put the fuel closer to where it needs to be. That should make it a little happier. About the O2 sensor... do I have this right: The way I understand it, when the bike goes into closed loop learn mode, it derives an AFV based on some average of feedback from the sensor which only tells it whether it is over or under 14.7 AFR. It then applies a fuel pulse correction +/- to the entire map based on that value, with the purpose of adjusting for variation in air pressure. Questions: Is it safe to assume that if I reconnect the O2 sensor, the bike will probably apply a correction that is leaner than the static dyno-tuned map? Is it also safe to assume that since the existing map is set for my config (after the K&N comes in), I shouldn't have any major lean or rich spots on the map after it applies correction for AFV? Is there a way to have it adjust itself a touch richer than 14.7? For example, my old Vstar would go into closed-loop at low engine speed and partial-throttle conditions, which would lead to twitchy throttle transitions and off-idle stumble. To fix it I put a resistor inline with the O2 sensor circuit "fooling" the computer into seeing a lean condition, where there really wasn't, and applying a pulse correction to richen it up. Can something like that be done on a Buell? Should I even worry about this? And if I shouldn't, is there a way to get the ECM to stop throwing a code whenever it can't see the O2 sensor? | ||
| Unlucky1 |
I put the K&N in last night. Obviously it was tuned for the higher flowing filter because it is a completely different bike, it seems much happier with more air. | ||
| Littlebuggles |
No more gas smell? Hopefully you see mileage improvements, these bikes are capable of 45-50+ mpg. Mine gets 43 around town and somewhere around 50 on the interstate if I keep speed reasonably controlled (under 85, when it runs...). Glad you got your hi flow filter in there, don't know much about engine management/ecm's and stuff but would have recommended that first anyway. (Message edited by littlebuggles on April 19, 2012) | ||
| Froggy |
That is correct.
Hard to say, depends on how good the tune was, but given this thread I'd say it was crap.
Not that I am aware of, but if you are tuned correctly, 14.7 is great.
Yes, but it all goes back to being a bandaid rather than a solution
This is what proved to me that the so called tuners have no clue what they are doing. According to their website, they tune with ECMspy, but apparently don't know they can tweak the O2 sensors or flat out turn them off rather than unplugging them giving you the issues you are having. If your bike was tuned correctly, you can have a nice 13-13.5:1 for great power when you are beating on it, but still maintain 14.7:1 when you are just cruising, allowing you to maintain great fuel economy, low emissions, and the bike will still have all the fuel it needs when that throttle body is wide open. My bike has a Micron exhaust, and a Race ECM with a modified fuel map for that muffler, and it easily gets me over 60MPG, and retains full use of the O2 sensor to compensate for altitude. Read over the tuning guide on ECMspy.com, you can improve the fuel mapping in the closed loop learn areas by leaning them out closer to stock levels, and re-enable the O2 sensor that way the bike functions as it should. Odds are the tuning shop got all the open loop areas fueled correctly so you wouldn't need to play with them, but the closed loop learn areas are probably way too right. With the O2 sensor disabled it can't lean out the mixture as you gain altitude, making it even richer possibly to the point of causing more issues. | ||
| Littlebuggles |
Love it, I only have to spit out some sort of half aye'd information or false data and some one is already in here to make it right.  Thanks for helping Froggy! | ||
| Froggy |
Nah, all you did was bump it back to the top, I started to reply last week, then shit happened and I forgot to come back and finish! |
