| Author | Message | ||
     Zuhl |
Hi! I am having some slight issues with my 2006 Uly and thought I would come here to see if anyone can help narrow my search for the solution. Basically, it has started to "miss" every now and then. It feels like it occasionally fails to fire and I am left with a deadspot in my power and then it almost instantly kicks back in. It is most noticeable when I am accelerating, but I am not sure if that is because I am in a lower gear so it is more pronounced. It happens in the dry hot air, so it is not rain induced. As background info it has a an aftermarket ECM and Jardine exhaust on it. It was on there when I bought it so I dont know much about it. I know he had to remap the system after the installation. If anyone can think of anything that I missed or recommend one culprit over the other, I would sure appreciate it. From reading the forums I have come up with some ideas of what could be happening: 1. Bad gas: No dice there. Have run through a couple of tanks. Was considering running some fuel injector cleaner in a tank, but I am doubtful that will work. 2. Spark Plugs: I have almost 8K on it and I think a plug change is part of the 10K service, so maybe they are starting to wear. Not sure if I should change them early and if so what plugs to use. 3. Plug wires: I think there is an issue associated with the front plug wire fraying and leaking current. I need to examine for this but am not sure where to look 4. ECM: I have heard about the factory one going bad and needing to be replaced. Not sure if this would apply with the one I have. I think it says something like PC Racing on it, but I would need to go pop off the seat to check. 5. Exhaust: I am betting that most of the glass has been blown out of that exhaust. I dont know if a lack of backpressure would cause a problem during acceleration though. I thought that could result in a bad idle, but I dont even know if that is applicable on fuel injected motors. I have seen it on older cars with straight pipes. Regardless I may repack the exhaust with stainless steel wool to make it quieter. Thanks for any help you may have! | ||
| Etennuly |
The front plug wire will lay across the steel idle adjuster cable, it will eat into the soft insulation easily. Does your bike have spacer blocks on the ecm bolts that hold the seat up off of the ecm plugs? Look for wear on the plugs and wires where the seat bottom could rub them. A proper TPS reset may be needed. Does it do the miss after riding about ten miles or so? | ||
| Thunderbox |
Pull off both the plug wires and inspect to see if the insulation is worn in any spot. If not good but if they are then get a set of 9 or 10 mm Magnacore wires. You could also have an intake manifold leak just in case you haven't thought of that one. | ||
| Sanchez |
One of my plugs died entirely with 8k on it. The front cylinder just stopped firing. You might also have fouled plugs. That's a cheap and easy replacement. I had to put in a new ECM at 29k. The seat had pushed on the ECM connectors until it broke a contact inside. Symptoms will vary there based on which contact breaks, but I'd be surprised if all you got out of that was occasional misses. | ||
| Armymedic |
When I first rode my bike home (700 miles), I had an intermittent rear plug. Changed it when home and smooth sailing ever since. Switched to Buell Pro platinums btw. | ||
| Methed |
Just got finished riding after application of the heat-shrink tubing mod on the fuel pump. Not sure how long the chaffing had been affecting things, but the engine chugs less and misses MUCH less when cold--an issue which I was going to change plugs over. Might be worth a shot, prolly easier than tipping the engine out and it really should be done if you haven't already. </soapbox>  | ||
| Mad_doctor |
I just changed my plugs and found a bad rear plug wire. I looked inside the spark plug boot, and it was full of rust. The reason I looked in the first place, was the rear plug had arc marks on the top. Runs MUCH smoother now. (I only had 5000 miles on the clock). | ||
| Zuhl |
Thanks for all the posts. This seems most noticeable when it is cold. But then, when it is cold is when I am leaving home of work and doing a lot of shifting and clutching in low gears, so I really feel it when it misses. After I get on the highway (10 min) I dont really feel it so much. I will check the plugs and ECM this weekend. Not sure how to do a TPS reset, but I will look in my service manual. | ||
| Chas1969 |
At higher elevations I hardly felt the shutter but the shutter is around 3000 rpms and on colder mornings 1st off from a cold engine. After 5 mins it is gone and seamless through-out rpms. My shutter (as above) I thought is pretty common XB happening. Chas | ||
| Zuhl |
This has been getting progressively worse on me. It will miss very bad at times and at other times run totally fine. Yesterday I opened her up and took out the plugs. To my suprise, the electrodes were both in perfect condition. However I found that the tip of the rear plug and the wire cage on the plug wire were VERY rusted. To the point where it was crumbling off. I am guessing that was the major source of my problem. Not sure how it happened though. Of course, in Houston, where even the one Buell dealer does not stock anything, there are no plug wires to be had. So I took my dremel and sanded all the rust off the wire cage to re-use it for now. I also got some dielectric grease to put on the tips to ensure good contact. So far I have only ridden it once for about 10 minutes, but it seemed much smoother with not misfires that I could tell. I eventually need to get a new set of wires on there just to be safe. My real concern is - what caused the plug tip and wire cage to corrode so bad? Dumb luck or something else? | ||
| Smac |
Hi Zuhl, I found your older post by searching for engine "misses". Your story seems very similar to mine. I own a 2008 XT with just over 24k miles. I started having the same problems you mentioned, so I changed the spark plugs and a new air filter which I thought would do the trick. The plugs I replaced seemed to have burned well with no signs of fouling. It was back to normal for about 75 miles or so, then back to the engine missing/studdering intermittently. Sometimes it runs fine, some times it acts up badly. It's usually the worst first thing in the morning and during accelerations from a stop. With that all said, did you finally come up with a solution to resolve the problem? Thanks, Sean |
