| Author | Message | ||
     Jhallgren |
Hey guys, I have been trying to track down a horrible surging stuttering at cruising speeds in the RPM range of 2900-4000 at constant throttle. I have been trying to resolve this issue since last year after I came back from a trip. Here is my first post on the issue http://www.badweatherbikers.com/buell/messages/142 838/789132.html?1475354452 I also ran a logged run earlier this summer and posted about it. IDS remapped my ECM using my log but the issue remains. That post is here http://www.badweatherbikers.com/buell/messages/142 838/809322.html?1501253894. This past weekend I found some time to do a compression test and a leak down test. The first night I performed the compression test with a cold engine. The results were as follows : Front cylinder first compression stroke was 95 psi Front cylinder final result after 7 revolutions was 164 psi. Rear cylinder first compression stroke was 95 psi Rear cylinder final result after 7 revolutions was 161 psi. I tried to do the leak down test with a cold engine and got odd results on the front cylinder. Here is a video of the results https://youtu.be/FfNWkiYPC24 I tired again the next morning this time I let the engine idle for about 10 minutes. I wanted to get some heat in the cylinders before I retried the leak down test as the manual says to perform the test with the engine at operating temp. Now the engine was not at full operating temp but I got better results. Here is the front cylinders results https://youtu.be/CJistRcMzPM Here is the rear cylinder results https://youtu.be/Ho6d-E-qvRg Actual results for front cyl was 17% and rear cyl was 14%. The manual says anything over 12% needs attention. My engine has 30,000 miles on it. Has anyone else here done a leak down test on their Uly? What results did you get? Also one other interesting find this weekend was the interactive exhaust valve might be slightly stuck open or have a weak return spring. I read on here that a leaking interactive exhaust valve in the muffler could cause some surging issues. I barely put my finger on the cable to take up some slack and heard a pitch change in the exhaust. Here is a video I took of it https://youtu.be/4ojiGsCKJjk Any ideas, suggestions, advice is appreciated. This is driving me insane and taking away the joy of riding. The Uly is the only bike I have and don't ever plan on selling it. As long as I accelerate or decelerate and don't stay at a constant throttle I am good lol. But that is pointless while I an in traffic. Sorry for the long post but I am trying to give all the info on what I have done. | ||
| Teeps |
Can you hear air escaping from throttle body or muffler during the leak test? | ||
| Hugie03flhr |
On a cold engine you will always hear air escaping for different areas. That's normal and your compression numbers are very good. You have to determine if it's fuel or spark that is causing your stuttering. An air fuel ration gauge might be your next step. Using a wideband sensor, you can see in real time if you are going lean or rich during the stutter. It can be as simple as an intake seal. On the other hand it can be ignition. That will be difficult to check. Maybe a long wire with a spark plug checker spliced in or those fancy glow wires that flash with the spark. Ride with the air box off so you can see. Good luck | ||
| Wademan |
Hows your AFV? Is it leaning out? Could point to o2 sensor issues. | ||
| Jhallgren |
Teeps, I could barely hear air coming from the intake and exhaust for both cylinders when I put my ear to the throttle body or exhaust outlet. I put my hand over both to see if pressure would build but it wouldn't build any pressure. Hugie, how does an air fuel ratio gauge get hooked up? At the O2? Never used one of those before. Sounds like a good way to check. I replaced plugs, wires and intake seals late last summer. I still suspect a intake leak but I checked last night and could not get the idle to change when spraying the flanges. Early this spring I got a check engine light for the fan. I replaced the fan and while I was in there I replaced the O2 sensor based on a recommendation from IDS about the stuttering issue. Wademan, my AFV two days ago was 94.5 but the temps were in the mid 80's here. I checked it again today when I got to work and it was 105.3 but the outside temp is only 68 today. Seems to bounce around a lot when I check it but I have never seen it go below 94 or above 105. | ||
| Wademan |
Jhallgren, that seems normal to me. Good luck with your issue. It can be quite frustrating, I know. | ||
| Jhallgren |
Well I wanted to test the theory of my exhaust valve in the muffler might not be fully closing 100% contributing to or causing the issue. I used ECMdroid and set the Valve to stay open when not in WOT. Other than the exhaust being a little louder, I didn't notice much change in surging or stuttering, if it all, it got a little worse. | ||
| Hugie03flhr |
I'm pretty sure the ECMdroid can monitor your O2 sensor. Set it up so you can ride and watch what it does when the surging starts. If it's the ignition, it should go rich during the stutter. If it goes lean during the stutter, it's fueling. If your reading goes crazy, it's your O2 sensor. | ||
| Jhallgren |
Hugie, I ran a logged run about 2 months ago. Not sure if you have Megalog viewer but it can be viewed using that. If you wanted to take a look, I attached the log to this post here http://www.badweatherbikers.com/buell/messages/142 838/809322.html?1501253894. Odd thing is I notice my O2 drops to 0 volts at times. Not sure if that's normal or not. I hope the O2 is not bad as I just put a new in this spring when I replaced my fan. | ||
| Natexlh1000 |
The Oxygen sensor has only one wire. That means that it needs the headers to be connected firmly in order to give it a ground. Often this would throw a code on my X1 before I revised the mountings. We're not dealing with a very beefy signal here. It wouldn't take much to mess it up before it gets to the computer. A rubbed through wire or loose connection would do that. But yours isn't throwing a code so I am at a loss. | ||
| Jhallgren |
Yeah its an odd issue I have been tracking down for a year now. Its still rideable but very annoying when cruising in traffic. I have checked the wiring from the connector to the ECM with my multi-meter doing wiggle tests and nothing seemed to change. I am not seeing any chaffed wiring but this winter I am going to rotate the engine for gasket maintenance and to try a new set Genuine James intake seals. I am going to better examine the wiring harness in the areas I can't see very well. | ||
| Natexlh1000 |
Ids remapped your ECM? So you're still working with the same computer? If you have a shaky solder joint in that box, it would do dumb stuff that doesn't make sense. This picture shows what's in our ECMs without being potted:  All it takes is one dry solder joint on one of the two connectors, and you're chasing ghosts. Is there someone around you that has a known good ECU of the correct vintage you could try? VERY easy to swap, TPS reset, and ride together. | ||
| Jhallgren |
I have a new IDS ECM. I bought one last year thinking that maybe my stock ECM might be the culprit. I relocated the new ECM right away but I have the same symptoms with the new ECM as the stock ECM. | ||
| 7873jake |
What @Natexlh1000 says... "All it takes is one dry solder joint on one of the two connectors, and you're chasing ghosts." "I have been trying to track down a horrible surging stuttering at cruising speeds in the RPM range of 2900-4000 at constant throttle." Exactly my problem for months. No errors in logs, very occult and cryptic issue. Lots of  and  New ECM made it disappear. | ||
| Natexlh1000 |
My 2008 was sputtering and misfiring as if the timing was off. I thought it was the ECU and since I am electronically inclined, I went about reflowing the solder joints in my ECU. It didn't change my symptom but it did allow me access to the pins that lead to the timing sensor on the front of the bike. I monitored the signal and it looked just fine on my oscilloscope even when the bike was misfiring. I rolled the dice and bought a race ECU from IDS and it just plain worked fine. Whatever fault I had didn't throw codes either. As far as the computer knew, it was doing the right thing. | ||
| 7873jake |
@Jhallgren I have to apologize. It appears that your post came through just before I had a chance to refresh the browser, creating the appearance of me giving you a suggestion that you've clearly addressed and which didn't fix the problem. I know the feeling, I just wish I had a way to help fix it for you. Damn. | ||
| Teeps |
Fuel pressure? | ||
| Jhallgren |
Checked the pressure and was at 50psi. I removed the pump and replaced the filter as well this summer but no change. | ||
| Hugie03flhr |
Jhallgren, if you are getting a zero reading from a hot O2 sensor, there's a problem. I'm battling an O2 sensor now that blanks out after 3000 rpm but I'm not experiencing any stutter. I'm still running a completely stock bike so I'm assuming my ECM goes to open loop and the tuning is close enough for me not to experience any problems . With the exception of a check engine light. Because you have a different tune and a slightly modified bike, your open loop tune may not match your set up. I'm guessing here but it the stutter coincides with the O2 reading zero or out of range numbers, this could be your problem. Every now and then every make bike has a corky insane problem and you may need to travel to find the wrench that really knows his stuff to sort it out. Good luck!!! | ||
| Steveford |
His TPS reading also goes berserk the same time the O2 sensor goes to zero. The TPS has slop in it. | ||
| Jhallgren |
It seems on my 09 there is no way to take out slop. I removed it and it is not spring loaded. It is a POT that moves and stays in what ever location you left it. The throttle return spring is what snaps it back to idle position since the TPS rides in a slot on the throttle shaft. Is your 06 TPS spring loaded. I have already tried loading the TPS but as I described, it cant really be loaded on my 09. | ||
| Tootal |
That's odd. If it's not spring loaded then any slop between the pin and the groove could cause a problem. I have an 06 and it's spring loaded. I don't know why they wouldn't want to do that. Anybody have an 08+ that can test theirs? | ||
| Jasonmcelroy |
I took mine apart recently when cleaning the intake tract. No spring on my TPS either. 2009XT Jason (Message edited by jasonmcelroy on August 31, 2017) | ||
| Steveford |
Call around to see who has P0279.3AA in stock and have them see if it's spring loaded. My bike has an 07 throttle body in it and the TPS which came out of it is spring loaded. Unless I'm full of it that should be the same part number in your 09. That .3AA number is discontinued so maybe they superseded it to one without a spring in a product cheapening measure. (Message edited by SteveFord on August 31, 2017) | ||
| Jhallgren |
Steve, after investigating, P0279.3AA is totally different. I checked St. Pauls website and P0279.3AA is for 2007 only. P0279.5AA is for 08+ models. The sensors are totally different looking. For reference here is P0279.3AA : https://www.sphdonline.com/products/p0279-3aa-genu ine-buell-throttle-position-sensor-b2p Here is the TPS for my 09 P0279.5AA : https://www.sphdonline.com/search?type=product&q=P 0279.5AA Also looks like the throttle bodies are a little different as well between 08+ and the earlier Uly's. When I had the throttle body out last summer to replace the intake seals, I figured I would swap out my TPS just in case it was contributing to my issue. No change with the new TPS. If there is anyone in the Chicago land or Milwaukee area's that would like to meet up and ride my uly and let me ride theirs for comparison, I am up for it. Also any one know a good Buell tech or HD dealership with a good Buell tech within a hundred miles of McHenry IL? I have had poor luck with any HD dealers around my locale. The only one that was OK was Ukes HD in Kenosha WI where I bought my Uly back in 2010. I went up there last year and they kind of shrugged me off and I didn't feel like they really cared. Maybe I got the service writer on a bad day, but I was highly unimpressed with they way I was handled. | ||
| Steveford |
The plot clots. You have the 1125 style, can't help you there. Maybe you got a bum one, anything is possible. If you put a Bosch O2 sensor in there I'd throw that away, too. O2 sensors don't go to zero volts unless they're going into the garbage can. I do not believe an erratic TPS would cause an O2 sensor to go to zero volts. It seems kind of unlikely that both a TPS and an O2 sensor would fail at the same time although who knows, maybe they did. I'd be inclined to take a look at the wiring in that area for a marginal connection or a frayed wire. It's always something really stupid. This probably only happens when it's hot. You could ride the bike for 50 miles, pull off the airbox assembly, hook the bike up to ECM Spy, start it up with a fan in front of the engine, use something to wedge the throttle open so it's running at around 3500 RPMs and start wiggling the wires around. Keep an eye on the TPS and O2 sensor and see when it goes crazy. That's the best I can do over a computer. | ||
| Jhallgren |
Thanks Steve, I appreciate the suggestions everyone has provided. I am going to stick with this. Maybe I will find the issue this winter when I rotate the engine for maintenance. Going to go over the harness where I can't see it very well. |
