| Author |
Message |
    
Cadhopper
| | Posted on Sunday, September 24, 2006 - 01:28 pm: | 
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OK, so I was on my way home from the Liberty open house yesterday evening and was about 150 miles into the 350 mile ride the bike started surging and backfired through the exhaust so bad that it stalled the engine several times. Needless to say I was getting a little nervous but I managed to make it home. The problem is very noticeable at a steady cruising speed but the bike runs good under heavy acceleration. The bike also surges at idle between 1000 and 1500 rpm's and sometime the idle will hang at about 2000 rpm's for a few seconds when I first come to a stop.
I suspect an intake leak but would that cause the backfire and stalling? Any other suggestions on what to look at would be helpful. Thanks |
Cadhopper
| | Posted on Sunday, September 24, 2006 - 01:32 pm: |
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I should also mention that I hooked the bike up to the VDSTS software this morning and the TPS setting look good and there were no error codes stored in the ECM.
(Message edited by cadhopper on September 24, 2006) |
Tomr
| | Posted on Sunday, September 24, 2006 - 03:21 pm: |
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I've had a similar problem with my '06 XB12Ss. My issue has occurred twice on the same road one week apart (maybe I should stay off of old NC 18?).
Both times the problem happened after accelerating for short bursts between low speed corners at around 2500 - 3500 rpm. The bike actually quit running for about 3-4 seconds, but started again (and backfired) after disengaging the clutch and then bump starting it.
I'm going to try to get it to the dealer this week.
Tom |
Cadhopper
| | Posted on Sunday, September 24, 2006 - 06:07 pm: |
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I went for another ride and the bike was still surging and bucking and I almost tucked the front end in a curve when the engine decided to cutout. I headed back home and checked for an intake leak using the propane method described in the manual but could not get the idle to change so I will pick up a can of carb cleaner and try again.
I'm starting to wonder if there is a problem with the fuel injection. When it died on the test ride and backfired it sounded like a rifle shot but started right back up when I hit the switch.
Edit - After doing another search I'm starting to think I may have a fuel pump issue. It seems this will cause most of the symptoms that I am experiencing. Anyone have any thoughts on this?
(Message edited by cadhopper on September 24, 2006) |
Tomr
| | Posted on Sunday, September 24, 2006 - 07:30 pm: |
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Funny (not really) I went for a ride this afternoon as well and had the same symptoms after running at about 2500 rpm for a while behind a slow moving vehicle. The bike seemed to run fine when it was not fully warmed up (about the first 10 minutes).
I could reproduce the problem by letting the engine decel for an extended period and then slowly rolling on the throttle. Full throttle seemed ok as did idle. Based on some other posts I've seen I'm starting to suspect the open loop / closed loop ECM transition - But as I said, I'm going to try to get it to the dealer as soon as I can.
I'll post what I find out.
Tom |
Cadhopper
| | Posted on Sunday, September 24, 2006 - 07:39 pm: |
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Tomr,
I'm going to call the dealer in the morning and drop the bike off as soon as they can look at it. I'll let you know what they find. |
Cadhopper
| | Posted on Tuesday, September 26, 2006 - 08:28 am: |
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Yesterday evening I decided to try another test ride after checking all the electrical connections and the vent line to the fuel system. So with my cell phone in hand (just in case I needed a trailer) off I went down the rode for a 35 mile ride. I decided to do a steady ride for about 8 miles and keep the bike in the 2500-3500 range to let the AFV reset but it did not seem to help.
As Tomr said, after the engine warms up the bike starts acting up so I would think that rules out an electrical short. Sometimes the bike starts loosing rpm's and feels like it's running out of fuel and other times it will start surging, bucking and backfiring through the exhaust until the engine dies. At first the problem only happened about every 50 miles but on this ride it was happening every about every 2 miles so it's getting worse. I did notice if I get the rpm's back above 4000 when it starts acting up I can feel the engine surge but it is less likely to die. The strange thing is the bike starts right back up every time. I also watched the instrument panel and lights to see if I was loosing electrical power but everything remained on with no flickering and the Charge Guard LED remained green the whole time so the bike is not loosing power.
I trailered the bike in to work today and will drop it off at the dealer this afternoon. I will be very curious to see what the problem ends up being and hopefully they will have the parts on hand to fix it quickly.
So all that being said would anyone care to take a guess at what the problem might be? |
Tomr
| | Posted on Tuesday, September 26, 2006 - 02:36 pm: |
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My dealer is overbooked in service all of this week, but I'm going to take my bike in tomorrow anyway in case they are able to squeeze it in.
I'll be anxious to hear how your situation is resolved.
Tom |
Cadhopper
| | Posted on Wednesday, September 27, 2006 - 07:09 am: |
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I dropped the bike of yesterday but I'm not sure how soon they will be able to look at it. The first thing the tech said was he thought it might be a short but I'm not so sure because it only happens when the bike is warm and running below 4000 rpm's but we will see what they find. I'm going to do some more reading tonight and try to figure out how all the sensors and fuel injection work so maybe next time I can figure the problem out on my own. I'll let you know as soon as I hear something from the dealer. |
Cadhopper
| | Posted on Wednesday, September 27, 2006 - 02:07 pm: |
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OK, after searching and reading waaaaay to many posts on this forum I came across one that said if the tach is jumping around when my engine starts cutting out that this means the Cam Position Sensor could be the culprit. Can anyone confirm this? Thanks |
Blake
| | Posted on Wednesday, September 27, 2006 - 05:41 pm: |
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I would say that it means that the cam position sensor may be the culprit. It could be a short or faulty/dirty connector or a bad ground among other things. |
Norcalbuell
| | Posted on Thursday, September 28, 2006 - 12:13 am: |
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I had the same exact thing happen to my 04 12r... what you described is the bike almost feel like its running out of gas or clogged injector or electrical type power cuttin in or out. It would surge at a constant rpm up and down.....Sucks donkey balls...Haunted me 2 different times and I lived with it way too long... Dealer set the tps a couple a times and seem to help a litle but would come back... Certain brand gas seem to trigger mine.
Ok this how i resolved mine, however im not quite sure the exact cause but this seem to fix mine and hasnt come back...
I thought for sure it had to be something in the fuel delivery such as injector, fuel pump etc. I took the air box off including the bottom portion that covers the TB, which means you have to unplug the AIR TEMP SENSOR that resides right next to the oil overflow hoses, forget the technical name for them.. Clean the throat of the tb real good with carb cleaner which is what i thought fixed it the first time..I checked all elecrical connectors around the tb which there are a shitload...
The Bottom line causing my grief, IMO (which i could be totally wrong but seem to cure mine) was the air temp sensor in side the air box was either dirty or might still be faulty and could start doin it again but the first time i think just unplugging and plugging the connector to it was enough to fix it..
The same symptoms started again after about 4 tanks of gas which some gas came from some back country gas stations.
After i put it back together i did the afv reset by crusing at 3500 rpm in 5th gear..Hasnt come back for 10-15 tanks of gas..
I hope that helps it should....
Chuck |
Blake
| | Posted on Thursday, September 28, 2006 - 04:57 am: |
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Just to be clear, TB = "throttle body"? |
Cadhopper
| | Posted on Thursday, September 28, 2006 - 07:49 am: |
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Thanks for the help guys. I spent around 5 hours reading through the service manual last night and have a much better understanding of the bike and how everything is hooked together on the fuel and ignition system. It's something I should have done before I took it to the dealer but I've been busy on other things. If they don't have any answers for me by Friday I may pick the bike up and do some testing myself this weekend.
I would sure love to get my hands on the schematic for the breakout box that they use in the manual.
(Message edited by cadhopper on September 28, 2006) |
Norcalbuell
| | Posted on Thursday, September 28, 2006 - 12:50 pm: |
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Just to be clear, TB = "throttle body"?
yes |
Cadhopper
| | Posted on Saturday, September 30, 2006 - 07:19 am: |
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Looks like I may have caught a break on the troubleshooting issue. As I was picking the bike up from the dealer today, because they had not had a chance to look at it, the bike would not start and the fan was coming on even through the engine was cold. The bike did eventually start but the computer trapped codes 11, 14, 15 and 44 so it looks like I may have a short in the BK/W or R/W wire which controls all the sensors for the closed loop side of the FI system or a bad ECM. So the mission today is to check bad connections or shorts in the main harness. Wish me luck, I going in. |
Cadhopper
| | Posted on Saturday, September 30, 2006 - 07:46 pm: |
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Well after inspecting, pulling, twisting and wiggling the wiring harness while hooked up to the VDSTS software and a multimeter I could not find any shorts or cuts. I decided to unplug all the connectors and check the pins which all looked good so I put everything back together and took a test ride and after 50 miles the bike ran perfect. For good measure I did a reset on the TPS and AFV and rode another 150 miles in varied conditions and speeds ( a max of 119mph on the GPS  ) and a few short wheelies for shock testing with no problems. 
So in the end was it just a bad connection  , I guess we'll see in another 500 miles or so. For now after a hard days work it's time for a good meal and a few of these  to celebrate the fact that my baby is running good again. |
Tomr
| | Posted on Sunday, October 01, 2006 - 07:27 pm: |
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Glad to hear it's running fine again. Mine's been at the dealer since Wednesday. At least the weather was perfect this weekend.....
Tom |
Tomr
| | Posted on Tuesday, October 03, 2006 - 11:51 am: |
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Well, the dealer just called me and said that after riding it a couple of times in different conditions that they could not find any problems.
I can understand the difficulty of trying to track down an intermittent problem, but I'm not feeling too secure about the reliability of the bike at this point. |
Cadhopper
| | Posted on Tuesday, October 03, 2006 - 02:16 pm: |
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It is hard to troubleshoot a intermittent problem. You might want to look close at the wires under the seat and see if there is any chaffing. The seat tends to rub on the wires going into the ECM. I also had some chaffing down by the bracket on the muffler where the chin fairing mounts.
Did they find any error codes stored in the ECM? |
Tomr
| | Posted on Tuesday, October 03, 2006 - 04:12 pm: |
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Thanks for the feedback. I'll check the wires under the seat and had noted the same thing.
I spoke with the dealer one more time this afternoon and they said that they did a TPS reset also and noted that there were no error codes.
Who knows, maybe the TPS reset will help (it seems to be a common thread).
I'll keep my fingers crossed.
Tom |
Tomr
| | Posted on Tuesday, October 03, 2006 - 07:59 pm: |
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Well, I picked up the bike from the dealer this afternoon. The Service Manager said that the TPS was at 5.2 and that they reset it.
Hoping that the problem was fixed, I got on the bike and dutifully headed down the interstate for 10 minutes at a steady 3700 rpm or so (I've read that this needs to be done).
I stopped for fuel and proceeded down a two lane highway through a small town without any problems. Just as I was thinking that the problem seemed to be gone, the same issue occurred (wild tach swings with stumbles followed by a loud backfire).
I noticed that the problem occurred after about 5 seconds of closed throttle engine braking after running at about 2800 rpm. I was able to reproduce the issue several times including later on the interstate(!).
Back to the dealer tomorrow.....
Tom |
Dave
| | Posted on Wednesday, October 04, 2006 - 07:41 pm: |
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"The Service Manager said that the TPS was at 5.2 and that they reset it."
I think the Service Manager is a bit misguided. The TPS is reset (told the butterfly is completely seated) is based on a 'reset' (position 0) signal. Then...there is an initial voltage setting that the idle thumb wheel is set to and corresponds to sufficient fuel for the bike to idle. After than, the idle is set to spec which would correspond to a 5.X voltage.
Reading a 5.2v based on a 1050 RPM idle really means nothing but normal.
DAve |
Tomr
| | Posted on Wednesday, October 04, 2006 - 09:32 pm: |
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Thanks for the post Dave - maybe I misunderstood.
It's back at the dealer this evening. |
Cadhopper
| | Posted on Thursday, October 05, 2006 - 05:58 pm: |
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Tomr,
Does your dealer have a dyno? They should be able to ride it on the dyno while hooked to the scanalizer. Also, I don't know if it will do any good but see if they can reset the AFV, it can't hurt. Good luck |
Tomr
| | Posted on Thursday, October 05, 2006 - 09:39 pm: |
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Cadhopper,
Thanks - The dealer Blue Ridge HD Buell, does have a dyno. The service manager mentioned it as well.
Very frustrating of course - the dealer can't reproduce the problem. I think they're good guys and are (nearly) as frustrated with the issue as I am.
I'll certainly ask about the AFV.
Thanks,
Tom |
Bigdaddy
| | Posted on Friday, October 06, 2006 - 07:55 am: |
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Tom,
I totally missed this thread. Blue Ridge has a Buell-centric manager/owner/co-owner (I don't know the exact structure.) He spent a number of years drag racing Buells -- his race bike used to sit right in front of the service desk. I haven't been there in a very long time and they're the closest HD shop to my house.
If I can be of assistance let me know and tomorrow I'm riding up to Blowing Rock to meet up with the C3 crew if you're interested.
G2 |
Tomr
| | Posted on Friday, October 06, 2006 - 09:27 am: |
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Bigdaddy,
I'd love to meet up tomorrow (if I have a bike...). |
Tomr
| | Posted on Monday, October 09, 2006 - 07:00 pm: |
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Well, I rode over 120 miles on Saturday with the local C3 group and the bike did not cut out or backfire at all.
I rode it to work today and was (once again) thinking that the problem was somehow cured - until... steady running at 2800 rpm (4th gear at 50 mph) yielded the same familiar symptoms.
This time I rode straight to the dealer and Chris (who I understand is one of the co-owners) got on the bike and rode it. He was (thankfully) able to reproduce the problem.
They have the bike now and I have a new loaner Firebolt sitting in my garage until the problem is resolved (by the way, the Firebolt is so much fun to ride that I nearly forgot about my aching back and wrists!)
Though I'm frustrated with the issue, I'm impressed with level of support I'm getting from the dealer.
Tom |
Cadhopper
| | Posted on Monday, October 09, 2006 - 07:22 pm: |
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Sounds like you have a good dealer and I'm glad he was able to see the problem. Hopefully if they can't figure it out someone from Buell will be able to make the trip down and get it fixed. It's also very cool that they gave you a loaner bike, I seriously doubt mine would. |
Toxic
| | Posted on Tuesday, October 10, 2006 - 03:27 pm: |
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I'm having a very similar problem...the dealer still can't get the bike running right. I have a post on here "Lemon Uly." |
Tomr
| | Posted on Friday, October 13, 2006 - 09:15 pm: |
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I picked up my bike from the dealer this afternoon. They replaced the cam position sensor.
They said that they were able to reproduce the problem before the change on the dyno and not afterwards, so I'm hopeful.
Anxious to ride tomorrow.
Tom |
Tomr
| | Posted on Saturday, October 21, 2006 - 07:38 pm: |
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Well - I'm declaring the bike fixed. In around 200 miles since the repair I've not had the issue show up again. The bike's actually running better than it ever has.
Now if I can just get past the shock of the rear tire being worn out at 2700 miles.... |
Bigdaddy
| | Posted on Saturday, October 21, 2006 - 09:05 pm: |
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Glad the bike's running right. Can't help you with the tire issue  Buy them 2, or 3, sets at a time and it only hurts once
G2 |
Cadhopper
| | Posted on Sunday, October 22, 2006 - 09:11 am: |
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Glad they figured out the problem with your bike. |
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XB12 Surging, spitting and backfiring through exhaust