running lean

[DualSportDad]

did you ever figure out your problem? i'm having the same studder between 4-5k. i think it's my o2 since it's just stuck at .48 volts. i changed it tonight and will have it running again tomorrow after i change the plugs.

i was just asking cause you said you just changed the o2 and plugs and started data logging but you had no studder while trying to data log.

 

[WhiskeyNick]

DualSport, I have not found the issue yet. Changing the o2 sensor didn't change anything. The last time I did a datalog I noticed a small studder a few times. It only seems to do it on WFO. I will try and find it on my datalog to see what is going on at that time. The other problem I have is on first start, it will spit and sputter and die. It takes 4 times of starting it to get it to keep itself running.
I'm going to take my bike to Christmas dinner tomorrow and do more data logging.

I think I'm going to try ecmspy and see if it will work with my bike, tunerpro requires a lot of research

I uploaded a short video of my last data log on youtube under whiskeynick250

 

[DualSportDad]

Thanks for the update. I'm about to take mine for a spin in a few min. I'll let you know if it helped mine.

 

[DualSportDad]

the new o2 and plugs fixed my bike. it runs good now. here's a link to my thread: http://www.buellxb.com/Buell-XB-For...2Scg/Troubleshooting/bogflat-spot-at-4000-rpm

have you reset your afv yet? is it still at 74 after the drive?

 

[WhiskeyNick]

I haven't figured out how to reset the afv value with tunerpro yet. What was the part # of the o2 sensor you used?

 

[DualSportDad]

Ntk 21002.

I don't have any experience with tuner pro so I'm sorry I can't help you there. I would think after some miles your bike would straighten itself out after a few miles if it was the o2. Mine did but then again my afv wasn't way off.

Id check your afv, if it's still way off I'd spend some time learning how to reset it.

 

[WhiskeyNick]

Matteson, to clear things up about the plugs. This was not a plug chop. These were the plugs that were in my bike when I bought it. So they are about 6 months old and probably 2000 miles. A plug chop is usually a new plug installed and only a few miles on it. Some people will put in a new plug and run it to wide open in 4th gear and kill the bike, let it coast to a stop and check the plug, This is not the case with the picture above.

 

[WhiskeyNick]

Finally figured out my problem. It was the tps. I picked one up from Napa # 2-16658. Not sure how much they cost from HD but I work for Napa so it was cheap.

When the problems first started I did alot of tps resets, everyone tells you to start there. Looking back you probably shouldn't need to do tps reset unless you change the tps or throttle cables. Not sure.

I rode my bike for a couple months without doing a tps reset and it seemed to run ok for the most part. It wouldn't die at start and would only hit the dead spot occasionally between 4-5K. I finally did a tps reset and BOOM started running like ****. The tps is a sensor that as long as it's sending a signal the ecm thinks it's working and won't throw a check engine light.

Replacing the tps requires removing the throttle body so if you don't have a good set of tools or a service manual you might want to bring it to someone.

 

[Negative]

Always love a good AFV or engine management discussion ... Theycallmecrash and Matteson about made me scald the inside of my nose with my morning coffee with the Sméagol comment .... hahahahaha ...

I think all the points I was going to bring up on the ECU's function and methods of engine management have just about been covered ... I throw in my +1 with the people suggesting you get yourself a custom tune whenever you get the money and the time man ... (that is IF it's still dropping the AFV waaaayyy low with normal running) ... Remember a LOW AFV means the bike is running rich ... a HIGH AFV means the bike is running lean ... the AFV is a percentage value that the computer applies to the entire map based off of what it reads and stores from your closed loop learning areas ...

Matter of fact I'm pretty sure I have a few dead sectors on my TPS as well as I have the same pop and stutter at certain throttle settings around 3.8k rpm ... I'm going to test the full range of my TPS today after work and look for blank spots ... also I've done a lot of work with ECMspy on my 03 XB as mine came with the shittiest pipe I've ever had the displeasure of riding with and a terrible 'custom' tune ...