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10-30-2012, 07:45 PM
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#1 |
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Adventurer
Joined: Apr 2011
Oddometer: 68
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TuneECU Injection Pulse reading - Screenshot
I'm trying to diagnose some rough running on my '07 990 adv. At idle the exhaust at the left pipe seems to be sputtering and weak. I already set the TPS to .57-.58v hot and sync'd the TBs as best as possible by matching the TuneECU map values at idle.
I was checking with tuneecu and I see the following: http://www.flickr.com/photos/8942711...ream/lightbox/ Given that there seems to be a difference in how the two cylinders are running, based on the exhaust feel and sound, the two different values for 'Injection pulse' seem to jump out. ~2.6 on the left value and 3.1 on the right value. I also noticed when I first started the bike the O2 reading on the left read consistently lower than that on the right. Does anyone know if this is normal? Anything I can check/test? |
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10-30-2012, 10:47 PM
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#2 |
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Zoob
Joined: Sep 2004
Location: Main Street, Shedd, Oregon
Oddometer: 984
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First, you should post this on the TuneECU thread.
Have you flashed a new map when this happened? My first map push from TuneECU was a bad one and it would run on one cylinder. Just pushing the map again fixed it and it ran fine.
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"Dad, can I get a motorcycle when I grow up?" "Son, you can't do both" |
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10-31-2012, 05:07 AM
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#3 |
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Gnarly Adventurer
Joined: Oct 2004
Location: left corner of VA
Oddometer: 448
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It appears your 02s are not disabled,so I would look for an air leak on the cylinder with the higher PW reading.
The 02 sensor is seeing more air and ramping up the pulse width in an attempt to correct. + what Zuber posted.. |
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10-31-2012, 09:04 AM
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#4 |
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Adventurer
Joined: Apr 2011
Oddometer: 68
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Ah good feedback. Sounds like a couple of tests might help:
-Load the open exhaust map w/ o2 disabled and see if the cylinder still feels weaker -Re-load the stock map and see if the issue is still there -See if there are any exhaust leaks at the header pipes (I did remove and remount those recently) Anything else I should check? |
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10-31-2012, 12:43 PM
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#5 | |
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Gnarly Adventurer
Joined: Oct 2004
Location: left corner of VA
Oddometer: 448
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Quote:
While running take a long pair of needlenose pliers and squeeze off all the vacuum lines to the affected cyl while watching the pulse width.Also check the SAS for leaks at that cyl. |
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10-31-2012, 04:43 PM
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#6 |
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Adventurer
Joined: Apr 2011
Oddometer: 68
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Just had a few min to do some checks...
I loaded up the akrapovic map and found that the sputtering from the left pipe stopped, however the exhaust pulse still felt stronger (just subjectively on my hand) from the right pipe. I'd have sworn they always felt about the same in the past but I don't remember really thinking about it before, so I don't know if this difference is normal or not. I really wish I knew if the difference is normal... (the bike does have leo vince pipes w/ an h pipe, so who knows). The injector pulse reading in TuneECU was still longer for cyl 2 than for cyl 1 with this map. With this map, cyl 1 MAP read about 20hPa lower than cylinder 2 at idle, but they're matched with the stock map - not sure if this would mean anything. I used in IR thermometer and the front cylinder header is about 20degrees warmer than the rear but they're pretty close with either map. I then re-loaded the stock map and the sputtering in the left exhaust pipe returned. I noticed in TuneECU that my voltage drops from about 13.1V to 12.5 when the fans come on. I saw it dip as low as 11.8 at one point. As the bike runs the O2 voltage would typically be in the .75-.8V range for both cyl but would drop to virtually 0 occasionally. I was looking to see if it correlated with the voltage drop when the fans came on but couldn't really tell if it happens around the same time or not. Next up will be to try big-t's suggestion of squeezing vacuum lines... not sure if I'll be able to access them with the airbox on or not but we'll see - definitely a good idea. In the meantime - anyone have any ideas as to why the injector pulse would still be longer with the akrapovic no-O2 map loaded? I guess this could suggest some leak in the vacuum hoses huh? Do you think my voltage drop when the fans come on is abnormal (ie - do I need a new battery?) THANKS!!!! |
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10-31-2012, 06:47 PM
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#7 | |
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Beastly Adventurer
Joined: Jun 2007
Location: Rough Rider Country...Bismarck ND
Oddometer: 1,020
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Quote:
How old is that battery... it looked fishy in your screen shot... [IMG] [/IMG]This is one of my first screenshots
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Originally Posted by d0gWateR Vagrant, vagabond, transient, hobo, bum. But park a motorcycle next to him and PRESTO! He's an advrider! Dusty screwed with this post 11-01-2012 at 12:02 PM Reason: typo |
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10-31-2012, 07:17 PM
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#8 |
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Adventurer
Joined: Aug 2007
Location: San Antonio, Texas
Oddometer: 331
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I have. A Signal dynamics voltage meter on my 990 and a new battery and a second fan. I notice a voltage drop to about 12.1. When the fans come on.
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Proud to be supporting Pyndon in the 2013 Dakar ! 2007 KTM 990 Adventure 2008 KTM 300 XC (plated) 2008 KTM 690 Enduro 1998 KTM 400 RXC (sold) |
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11-01-2012, 11:37 AM
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#9 |
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Adventurer
Joined: Apr 2011
Oddometer: 68
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Hey Dusty thanks for the comparative screen shot!! That is very helpful and it does look like your O2 values are much more even. Mine are crazy because they'll just drop all of a sudden to almost 0 and then fluctuate a bit, then come back to the 0.7-0.8V range, then drop again, and the injector pulse doesn't really seem to move in lockstep with the O2 value. I really don't have any clue how to diagnose this other than fiddling with vacuum hoses at this point. I suppose I could switch the 2 O2 sensors and see if that makes a difference, but ugh I think I'd have to take the whole exhaust back off...
So were you saying you thought that the exhaust should or shouldn't feel the same at the exhaust pipe? Dirtjack - thanks for the info on the voltage - I've got the 2nd fan also so maybe my levels are reasonably normal - at least not high on the list of possible culprits... |
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11-01-2012, 12:01 PM
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#10 | |
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Beastly Adventurer
Joined: Jun 2007
Location: Rough Rider Country...Bismarck ND
Oddometer: 1,020
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Quote:
From memory i dont think mine felt equal from day one... different lenths of pipe, bends?
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Originally Posted by d0gWateR Vagrant, vagabond, transient, hobo, bum. But park a motorcycle next to him and PRESTO! He's an advrider! |
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11-02-2012, 08:28 AM
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#11 |
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Adventurer
Joined: Apr 2011
Oddometer: 68
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Thanks dusty - that gives some peace of mind.
I read online somewhere yesterday that narrow band o2s are kind of binary and will typically flip from low to high voltage when the af ratio becomes rich or lean. So some fluctuation is probably normal there too when running on o2s. I tried a stethoscope and shooting some starter fluid around to look for vacuum amd exhaust leaks but nothing conclusive. It does seem like a vacuum leak is the most likely culprit based on the symptoms I noticed the vacuum hose that comes off of the t at the intake manifolds and runs to the pump under the dash is kinked a bit, but not leaking - I wonder if this could cause running One way or another looks like I've gotta start taking stuff apart to get access to those hoses |
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11-02-2012, 10:19 AM
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#12 | |
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Gnarly Adventurer
Joined: Oct 2004
Location: left corner of VA
Oddometer: 448
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Quote:
How about disabling the o2 s with Tuneecu and see if that evens out the injector pulse ? If it does I would bet on an air leak,maybe the SAS leaking air into the exhaust..at one of the cylinders.. or possible a dirty injector not atomizing the spray well enough for a good burn
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11-02-2012, 02:08 PM
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#13 |
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Beastly Adventurer
Joined: Jan 2007
Location: Lake Tahoe
Oddometer: 2,169
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I think your reading way too much into this. My exhausts were never the same either. Their different lengths and have a crossover. I'm reading this thread off my phone so I couldn't make out your screen shot to well. Injector pulse width should be different. Cal 1 is the rear and runs hotter do it should have more fuel. Injector pulse width is done in percentage of available time to open the injector. We are talking maybe 20 milliseconds here. If cylinder one is 2.6% and cylinder two is 3.1% we are talking about 1/2% of 20 ms. You injectors probably aren't even matched to within 3%.
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11-02-2012, 02:34 PM
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#14 |
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Gnarly Adventurer
Joined: Jan 2008
Location: Midlands UK
Oddometer: 366
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I would guess air leak or the throttles are not balanced - or not close enough to get the pulsewidths very similar.
Can you get a reading while riding the bike with more airflow going through the carbs? If you are happy there is no air leak there should be an adjustment to balance the throttles at idle (sorry 950 owner don't know the exact layout of the 990's) you could try adjusting that until the pulsewidths are the same. - also make a note of the idle is smother or not (should be smoother if you are balancing them). The correct way is to balance the air pressure at idle with pressure gauges of course... |
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11-03-2012, 08:55 PM
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#15 |
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Adventurer
Joined: Apr 2011
Oddometer: 68
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Yeah I've come to find I think the pulse length being different is normal.
The real problem is that the bike hunts around in RPMs at idle and there is a sputtering sound like it's missing from the left tailpipe. So I was just looking for anything in tuneecu that might help point me to the cause of this issue. I did turn off the O2s at one point and the sputtering sound does stop when I do that and the idle seems more stable but still not rock solid. One thing I noticed is that the rpm really drops and the bike seems to struggle after it warms up and I hear the solenoid click for the SAS pump at the back of the airbox. This wouldn't impact A/F ratio though would it? I thought it is just pumping fresh air into the exhaust - so why would it cause an rpm drop and the bike to start stumbling? hmm |
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