misfire on cylinders 1 and 2?? any ideas

gsxr1216

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2002 busa i'm getting a idle misfire on cylinders 1 and 2. at idle they are running 220 degrees. cylinders 3 and 4 are running at 420 degrees. i replaced all 4 plugs and no difference.

i compression checked it and all 4 cylinders are within 5 psi. i removed injector harness one at a time and when 3 or 4 is removed the bike almost dies. i removed plug to coils one at a time and when 3 or 4 is removed bike almost dies.

i swapped coil sticks around and still no difference 1 and 2 stay cold and misfire. it seems when you bring the rpms up that they smooth out some? is there any specific sensor or something that would only affect 1 and 2??

any other ideas on what to look for ??
 
Yer testing has not narrowed it down to either spark or fuel. I would do that first.

Someone smarter than me may have the fast answer.

Do you have a nearby Busa Bro you could swap out ECU's with for a qwik test?

RSD.
 
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