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XB12XTC
08-27-2009, 06:18 PM
Folks,

My 2008 Uly XB12XT has been giving us fits. Several months ago it began demonstrating the following symptoms:

After running the bike at freeway speeds in moderately hot weather, I shut it down for about ten minutes. When I re-start the bike it goes into a high idle mode (1500-2000 RPM). When the idle finally comes down, the bike won’t stay running unless I roll on a little throttle. It coughs and bucks until I get up to speed. Occasionally the CHECK ENGINE light comes on. When it does I pull over, shut down the engine, and restart the bike, and the CE light goes out (???).

Took the bike back to the dealership and they did a TPS reset. This didn’t help, and I took the bike back again.

This time the O2 sensor was identified as defective. The dealer shop replaced it and recalibrated the ECM. Both of these services were provided free under warranty. A curious phenomenon: since the ECM re-flash, the rear-cylinder fan doesn't run at all after I switch the engine off.

Picked the bike up two weeks ago, and didn’t have much of a chance to drive it since I was on several business trips. Rode it yesterday, and it had the same problems as described above. HELP!!! The bike ran fine for the first 3500 miles.

I suspect a bad Idle Air Control motor (or its O-ring) or a bad TPS sensor. This problem happens most frequently when the engine and outside temp are hot. I’m beginning to lose confidence in the machine...

By the way, I've got the right side air scoop.

Any suggestions?

07Bolt
08-27-2009, 09:43 PM
Backtrack your riding habits up to the complications w/the Uly. Ever left bike on a few hours? Diagnos some charging modules. Check for engine codes. Do a wiggle test,bike running,with the IAC. The CE light comes from the ECM. The TPS gets 5 volts from the ECM too. Also,leaky exhaust=rich gas mixture.

Are u selling the scoop??? :D

Stevenc150
08-28-2009, 02:58 AM
Check you're ground connections and for wire chafing in general. Trill found where his ECM wires were shorting against the frame:

http://i92.photobucket.com/albums/l21/surfstylez/ecmshort.jpg

If nothing is found, I'd try trouble-shooting the bike with ECMSpy and go from there. It will display past & present CE codes.