Have an 05 ultra FI that has me stumped as well as 2 Harley mechanics. Initial start up will run great cold, but as soon as it gets hot it will start to cough and ocasionally die, running down the highway it does ok, but when I come to a stop or slow my rpm's the bike begins to cough and stumble. I have SE tips, SE Air intake, stage 1 download with a new fuel tuner added (thought that was the problem) also have new internal fuel tank line and external fuel line, new fuel filter, new intake seals, changed IAC,TPS, IAT sensors as well, made no change. I took the bike to Harley shop, they ran the diagnostic and came up with nothing, the bike died and coughed on them, they pulled up a IAT code and tried a new sensor,did not work either, had everyone stumped. Took it to another Harley technician that sprayed carb cleaner and hopefully found the problem being a injector, would run better by spraying it from left side of bike directly at injector while shielding the intake. Before I bought the bike I was told it had been sitting for 2 1/2 years and the injectors were pulled and soaked in carb cleaner for days. O-rings looked good on the injectors when pulled. Can the injectors be damaged by cleaning with carb cleaner and do the symptoms indicate a possible injector problem? I am becoming overwhelmed financially as well as the mechanics becoming fustrated not finding the problem. They have bent over backwards to help me out. Dealership did not even charge

 

Kinda sounds like a compression leak around the injector. Are the threads good? Possibly a leak in a head gasket that opens with heat expansion of the parts?

 

probably intake gaskets. that's why when they spray gum cutter around the injectors it changes. the intake gaskets are leaking and sucking in the carb cleaner riching the lean condition at idle.