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Wolk625
Posted on Thursday, March 28, 2013 - 11:18 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

So I've posted a few threads in the past of my attempts to keep my AFV up - I swapped out my injectors then replaced my intake seals, which I believe I finally have done successfully (and was misdiagnosing a bad seal with over-spraying through the valley to the intake...). I've decided to start logging some data to see if anything funky is going on with the electronics. So far I've only made one test - was warmed up to full temp and I reset the AFV to 100 before taking off. I rode for 20 mins and came back to review everything. The AFV stayed the same this time, so I'm pretty sure whatever is happening is on cold starts. One thing I did notice in megalog was the graph for the O2 sensor was pretty sporadic - is its output signal supposed to be pretty smooth/linear or is it normal to be spike-y? What other data inputs should I be paying attention to for clues for diagnosis? I'll try to get data from a cold start tomorrow morning.

as always, thanks ahead of time
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Kevmean
Posted on Friday, March 29, 2013 - 08:50 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

AFV doesn't have to be 100 , any deviation from standard intake or exhaust or even altitude will mean it is either higher or lower,how low is it ?
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Wolk625
Posted on Friday, March 29, 2013 - 11:57 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

^- right, so what I'm hoping to do is to observe my data trends in how they compare with the AFV's changes and see what's happening. What I'm hoping to accomplish is finding if a faulty or abnormal sensor reading is skewing my tuning and causing the familiar "cough" condition, or, if not a sensor itself, point me in the direction of the real problem. I figure finding the problem through the data is a more sensible route than throwing money and effort at random things until it works.
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Oldog
Posted on Friday, March 29, 2013 - 12:58 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

The o2 oscillates, think about it,
you get a blast of hot exhaust gas, then the temps drop and you get nothing, followed by another blast of gas.

hot cold hot cold hot cold, so it should not be steady its output varies with temp and o2 content of the hot end gas referenced to the outside air...

there will not be output until its warmed up.....
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Wolk625
Posted on Friday, March 29, 2013 - 01:56 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

So I was able to do a cold log, and before I started I noted that the AFV was at 85 before I started. I reset it to 100 for experimental purposes and started on my morning commute. This is what I'm looking at:



This is the area I'm having the most trouble in the tune, and it's probably best shown on the top graph by the playhead - the rpm's begin to fall and I apply generous amounts of throttle with little to no effect on the rpm. It then "pops back" after a hard jab and I let off.

To my eyes, it seems like the problem could be somehow related to the EGO Correction/Gego, but I am a bit wary of the "correctness" some of these data plots - it also claimed I was going between 224 and 229mph while parked.... Does this data look indicative of anything obvious to anyone?
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Oldog
Posted on Friday, March 29, 2013 - 03:52 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Try a graph with the RPM, Throt, O2 Volts, ET,
the curve your o2 is showing is odd

the ones I have seen on VSDS are almost sawtooth patterns as the speed goes up
the form gets finer and finer

the O2 sensor output is 0-1 V iirc
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Firemanjim
Posted on Friday, March 29, 2013 - 11:27 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Remember, on these bikes really the only thing that will skew AFV down is a bad engine temp sensor---maybe a bad O2 but they usually read higher as they go, ETS telling bike it is cold and adding start-up fuel . Everything else skews AFV the other way.
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Wolk625
Posted on Saturday, March 30, 2013 - 12:33 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

The first graph I posted was at 6x zoom, so it probably could look a little funny. Here's another one, 1x zoom with a different data arrangement. The rpm hump to the right of the playhead is the same as the first one.

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Wolk625
Posted on Tuesday, April 02, 2013 - 11:00 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

So I did some more digging and some more thinking.. If my AFV is dropping, it is attempting to correct for a too rich situation. As well as what was mentioned already, High altitude, high temperature operation, incorrect ignition timing or TPS zero setting, high fuel pressure or a leaking injector can do that. Most of those I can rule out, but it made me think about how the O2 references the tables and their values to compare its value to come up with the AFV - so.

I think one of my enrichment tables could be goofed up. So a couple questions on those (may be worth a new thread) - what kind of values should the cold start enrichment table have? Is there a separate warm-up enrichment table or are they the same thing? Any other enrichment tables that I should be considering? Almost to the point of just de-activating the O2 and seeing what happens
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Wolk625
Posted on Thursday, April 04, 2013 - 03:44 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

so an update. What I did end up trying was turning the o2 off, added 5% to everything in the closed loop area and bumped the accel enrichment corr at 2500 rpm from 20 to 25%. It started up way easier, ran a lot more smoothly with no 3k stumble, but still seemed to lack that "punch" - kinda cushy but it was happy. the CEL came on for the o2, of course. I decided to try turning it back on and see how it would react to the new maps, and it still ran happy but cushy but when I returned the AFV was down to 85 like before..

Where do you think I should go from here?
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Two_seasons
Posted on Thursday, April 04, 2013 - 07:20 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Like Firemanjim said, and I concur, replace your ETS.

American Sport Bike has them...
http://www.americansportbike.com/shoponline/ccp0-p rodshow/17035.html Check out the socket at the bottom of this link. Helps to get old one out and new ETS in.
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Jramsey
Posted on Thursday, April 04, 2013 - 08:38 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

'99-'00 a 1/2" wrench works, '01-'02 which are "down the chimney" require a modified deep socket.
Pic of '99-'00 ets.


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Alfau
Posted on Friday, April 05, 2013 - 03:48 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Rear header seal is leaking?
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Two_seasons
Posted on Friday, April 05, 2013 - 04:45 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Somewhere along the way in the Model Year 2000 build at BMC they must have changed the head design regarding placement of the ETS, as my 2000 X1 has the recessed ETS hole.

Wolk, check yours to see whether you have the exposed, like Jramsey's photo above, or if your ETS is recessed. Obviously, if your ETS isn't recessed, you won't need the socket.
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Buellistic
Posted on Friday, April 05, 2013 - 11:07 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

What does AFV stand for ???

(Message edited by buellistic on April 05, 2013)
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Mbsween
Posted on Friday, April 05, 2013 - 11:57 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Adaptive Fuel Value


quote:

The AFV (adaptive fuel value - a number stored in the Buell ecm: 100 = baseline, 110 = more fuel, 90 = less fuel). The AFV is checked or reset during steady cruise between 3k and 4k rpm. This is in closed loop where the 02 sensor is monitored to detect if the AFR (air/fuel ratio) is rich or lean compared to 14.7:1 AFR. In closed loop, if the AFR is detected to be too lean, say leaner than 14.7 for most of the time, then the AFV number will be increased. Similar if the AFR is too rich in closed loop then the AFV number will be decreased. In this way, the Adaptive Fuel Value does exactly what it is supposed to do, that is, tune the ecm for different altitudes, seasons, whatever. This is all good so far. Now the important bit is that the AFV is used to scale the entire fuel map, not just the closed loop area.


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Buellistic
Posted on Friday, April 05, 2013 - 12:26 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

"THANKS" Mbsween !!!

Would you not think that if the REAR HEADER GASKET PN 17048-98 and/or the INTAKE GASKETS PN 26992-99 were bad or going bad would cause a big effect on the AFV ???
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Wolk625
Posted on Friday, April 05, 2013 - 02:10 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

I just changed the intake seals and have tested and confirmed them to be sealed correctly. I can re-replace the exhaust gaskets and rebuild the rest of the exhaust and see if that may help. Looks like I have the exposed version of the head temp sensor.
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Buellistic
Posted on Friday, April 05, 2013 - 08:36 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Wolk625 have you CHECKED THE TIMING ???
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Wolk625
Posted on Monday, April 08, 2013 - 05:52 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

So out of curiosity I thought I'd check the resistance on my head temp sensor and it looks like it's likely out of spec (supposed to be between 33761 and 74328 ohms cold while mine's floating around 77k). I'll go ahead and hunt one down and post results when I get it installed.
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Wolk625
Posted on Monday, April 08, 2013 - 06:26 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

^scratch that. that range was for 69-90 degrees, I tested it slightly colder than that ~62 degrees. Might be ok afterall. Maybe....
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Firemanjim
Posted on Tuesday, April 09, 2013 - 01:39 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Intake seals will skew AFV the other way,Just replace the temp sensor and see what happens.
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Wolk625
Posted on Tuesday, April 09, 2013 - 11:29 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Today the weather was bad so I figured I'd replace the exhaust gaskets. When I removed the header, I found a ~1 inch split extending from where the middle cross brace connects the two sides.. I spent a good amount of time taking care to tack-weld it closed and re-assembled everything. I was only able to let it idle in the garage to check if they were sealed good and it seemed like they were doing the job. I'll be able to test ride it when I'm not in a snow-nado warning anymore... (temp sensor is ordered and on the way, just doing some other odds and ends in the meantime)
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01x1buell
Posted on Wednesday, April 10, 2013 - 12:43 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Did you TACK weld it or weld it SOLID?
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Wolk625
Posted on Wednesday, April 10, 2013 - 10:57 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

sorry, bad wording there - solid tack in the middle, cooled it, then worked in full horseshoe patterns filling each side one at a time. I only did it that way because of the weird gap shape and I wanted to be sure it completely filled in the middle. surface tacks would be silly and would just shake off
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Wolk625
Posted on Thursday, April 11, 2013 - 07:43 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Some good news, I bundled up and rode to get the temp up - checked AFV and noted it was around 82. I reset the TPS because I had removed the battery for more room during the header uninstall/reinstall so I had "lost" my TPS set point and I left the AFV alone. I followed that up with a 25 minute ride, and ran fantastic the whole time with a super smooth powerband. When I came back the AFV had risen back up to 99 - that's the first time it's actually risen on its own since I've owned it. I'll keep riding it and see how it behaves in the long run but for now I'm pretty happy.
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Kevmean
Posted on Friday, April 12, 2013 - 08:21 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Just a point to remember ,disconnecting the battery does not lose the TPS setting ; ) .......likewise you can remove the ecu from the bike and refit it and it will still have the same TPS setting.
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