| Author | Message | ||
     Rhun |
I have a XB12S 2008 it runs like crap when cold. It sputters, pops, stalls or flat won't idle. Even when warm there are several flat spots when riding a little aggressive. Sometimes it sputters and pops also frequently at inopportune moments. To make diagnosing even more difficult sometimes every thing works great. I have the fourth ECM patch 'Z'. Each patch has helped a bit for a while. So if you have had a sick 08 or 09 and replaced some parts like the ECM, fuel pump, ignition, etc please let me know. I haven't left it with my dealer to diagnosis, yet as a sick bike is still better than no bike; but I know they are struggling with others also. HELP!!! | ||
| Mbo54 |
1. I would try replacing the plugs, they may be fouled. 2. I had a very similar issue with my '07 12S. I took it in to the dealer and they diagnosed it as: cable from TPS to ECM was grounding to cylinder head intermittently as the engine vibrated under load. They told me the cable must've not been routed correctly at factory. Mine was still under warranty at the time and I'm guessing yours probably still is so I would take it in. | ||
| Froggy |
In the Uly board a few members had the IAC and ECM replaced and seems to resolve their issues. | ||
| Xbrfirebolt |
Last week my dealer just replaced the ECM and that seemed to help. August '07 build date on my XB12R. | ||
| Rhun |
the rear plug fouled a while back and both plugs were replaced. What is an IAC? | ||
| Etennuly |
IAC = Idle air control. It is a valve controlled by the ECM for idle air/fuel management in all kinds of running conditions. | ||
| Ironhead1977 |
my 08 uly is in the shop 2nd time for those same flu like symptoms.we'll see what happens. | ||
| Zatco81 |
Been ridin with any Harley's lately??? May be swine flu.  | ||
| Srwitt |
Try different spark plugs, my bike came with a single electrode HD branded plug, I replaced those with a Buell branded splitfire style plug, bike runs way better, mileage is still crappy but it runs better. 08 12R | ||
| Bikertrash05 |
I traded my bad 08 for a good 09.  | ||
| Rhun |
Thanks Etennuly, I was sure that IAC didn't stand for inside air conditioning.  Ironhead: Let us know what they find. | ||
| Brandon_m |
Rhun, I feel your pain. My '08 Scg has operated that exact same way since the day after I brought it home. Spark plugs are definitely not the cause. The dealer's cure all is changing the plugs. I should have bought stock in harley plugs. If it's a plug issue, something is causing it (I just said "plug" alot....plug). Have you made any mods? Only thing I've done was K&N and a Jardine. Ran like garbage before and after the changes. Does anybody know how many ECM reflashes have been released for the '08 XB's? | ||
| Tmall |
I had your exact same problems. It was a bad TPS. Had it replaced, bike runs like a champ. No stuttering, sputtering, stalling or irratic idle. My buddy's 08 had the same issues. Tps replacement fixed it. The bike wasn't showing any codes. It just ran like shit. After they tried several things, they went with my suggestion and replaced it. My milage also went up.. From about 180kms a tank to 210. | ||
| Froggy |
Ouch 210KM a tank? My gas light usually comes on at a tad under 400KM on my 06 Ulything. Even with the smaller Firebolt tank you should be getting 250KM before even thinking of gassing up. | ||
| Earwig |
If it is an 08, why not bring it in and have it fixed under warranty? | ||
| Xbgeorge |
My 08 XB12R runs like a$$. I get a cough at 2100 rpm. Between 4100-4500 it just will not go, unless it is full throttle. It gust stumbles away in that range. I can't even keep it at a steady speed in that range. In the last week it has backfired four times at 4500. This was no normal cough or pop. It scared the crap out of me. Also, mine runs so damn hot, the frame burnt my legs again yesterday. I was wearing thick jeans too. I need to take it in, my warranty runs out in August. | ||
| Brandon_m |
Dealer says it's because of the air filter and exhaust. I know it's not but I'm at their mercy. The last time I had it in I was told it was running rich and it was causing partial fouling of the plugs. In that same conversation the story changed to the bike running lean which was caused by my K&N and exhaust. I questioned it but they stuck to it. Fine, whatever... I drove home and brought my stock filter back. On the way back they called me again and said the bike was running great. I asked if they put a paper filter in and was told "no, we're running it without a filter." WTF?!?!?! So aside from you running by bike around without a filter, you tell me it's too lean and then remove the filter all together? Are you serious? Long story short the service manager tried to charge me for 10 hrs labor because I caused the problems by altering it from stock form. But since he's such a nice guy he only charged me to change the plugs (which i changed the day I dropped it off). Taking it to my particular dealer only costs me money for my "warranty work." And unfortunately, the next nearest Buell dealer is well over 500 miles. It's absurd. I'm even afraid to ask about the ECM reflash. | ||
| Rhun |
I'm also wondering if the problem is more prevalent in States where you can't get 93 octane premium gas, like Kansas. |
