Motorcycle Repair: sputtering and backfiring thru intake, intake leak, sensers

Question
have a 2005 softail classic fuel injected with 18000 miles and bone stock. bike is running extremly rough and sitting back thru the intake. pulled spark plugs and found covered in soot but not wet. changed plugs and air filter starts up fine now. but as it idles down it starts to spit and sputter then die. with the air filter off can see the backfire thru the throttlebody. checked resistance on the ignition found no problems. any suggestions?

Answer
There are a couple of things that can cause the above problem. Coil is bad, plug wires are bad, and intake leak. You can do a OHMs test on the coil and plug wires and check the intake leak by starting the bike and spraying a little carb cleaner around the intake. If the RPMs go up then the intake is leaking.
If its none of the above you would need to have a dianostic run on the bike to determine what the problem is. One of the sensers might be going bad. With the dianostic you can see which one
Good luck and happy riding
Mike