Buell 2008 XB SERIES Electrical Diagnostics Manual page 102

Misfire at Idle or Under Load (Part 1 of 2)
2-52 2008 Buell XB Diagnostics: Engine Management
Is fuel contaminated?
YES
Drain and flush fuel
tank. Refill with fresh
fuel.
YES
Check for:
Faulty, worn or cracked Spark Plug(s)
Spark Plug fouling due to engine
mechanical fault.
Faulty or poor connection at Spark Plug.
YES
Ignition Coils should be
3
free of carbon tracking.
Are they?
YES
4 Switch Ignition Coil with
unit known to be good.
Perform spark test.
Did spark jump gap
during engine cranking?
YES
Original Ignition Coil
is faulty. Replace.
NO
Use Spark Tester to check Spark Plug
1
Cables. See 2.12 ENGINE CRANKS
BUT WILL NOT START.
Did spark jump gap on both leads?
NO
Check resistance of each
2
Spark Plug Cable that did not
fire the Spark Tester. Also,
check for faulty spark plug
wire connections and wire
boots for carbon tracking.
Are wires OK?
NO
Replace faulty
Spark Plug Wires.
NO
Replace
Ignition Coil.
NO
STOP
Go to Misfire at
Idle or Under Load
(Part 2 of 2).
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