
2.16
MISFIRE
GENERAL
Misfire at Idle or Under Load
Misfire conditions may be caused by:
•
Battery condition and connections.
•
Fuel system problems. See tables under
.
DIAGNOSTICS
TOOL NAME
PART NUMBER
SPARK TESTER
HD-26792
HARNESS CONNECTOR TEST KIT
HD-41404-B
Diagnostic Notes
Each reference number below correlates to a circled number
on the flow chart(s).
Wipe up spilled fuel and dispose of rags in a suitable
manner. An open spark around gasoline could cause a
fire or explosion, resulting in death or serious injury.
(00518b)
1.
See
. A SPARK TESTER (Part No. HD-26792)
must be used to verify adequate secondary voltage
(25,000 volts) at the spark plug.
a.
Turn ignition switch OFF.
b.
Remove spark plug cable from spark plug. Visually
check plug condition.
c.
Attach cable to spark tester. Clip tester to cylinder
head bolt.
d.
While cranking engine, watch for spark to jump tester
gap on leads.
e.
Reinstall and repeat procedure on other spark to jump
tester gap on leads.
2.
Perform spark plug cable resistance test.
a.
Remove spark plug cable from spark plug and ignition
coil.
b.
Using an ohmmeter, touch probes to terminals on
each end of plug wire.
c.
Compare resistance values to
. Replace
cables not meeting specifications. Reinstall and repeat
procedure on other spark plug cable.
3.
If carbon tracking is evident, replace ignition coil and
inspect spark plug wires. Wires must be clean and tight.
Excessive wire resistance or faulty connections can cause
ignition coil damage. See
.
4.
This test can also be performed by substituting a known
good ignition coil for one causing the no spark condition.
The ignition coil does not require full installation to be
functional. Verify faulty ignition coil by performing resist-
ance test. See
2.37 DTC P2300 (24), P2301 (24), P2303
.
5.
Use HARNESS CONNECTOR TEST KIT (Part No. HD-
41404-B), gray pin probe and patch cord.
ed01468
Figure 2-43. Spark Tester
Table 2-25. Spark Plug Cables
FRONT & REAR
SPECIFICATION
5.75 in. (146 mm)
Length
1,430-3,360 ohms
Resistance
2-50 2008 Buell XB Diagnostics: Engine Management
Summary of Contents for 2008 XB SERIES
Page 1: ...2008 Buell XB Models Electrical Diagnostics Manual 99493 08Y 2007 Buell Motorcycle Company ...
Page 4: ...Blank Text Here ...
Page 6: ...NOTES ...
Page 14: ...NOTES ...
Page 50: ...NOTES ...
Page 72: ...ed01568 Figure 2 16 Checking for Leaks 2 22 2008 Buell XB Diagnostics Engine Management ...
Page 202: ...NOTES ...
Page 224: ...A 22 2008 Buell XB Diagnostics Appendix A Connector Repair NOTES ...
Page 225: ...SUBJECT PAGE NO B 1 CONNECTORS B 1 B 2 WIRING DIAGRAMS B 3 APPENDIX B WIRING DIAGRAMS ...
Page 226: ...NOTES ...
Page 232: ...Figure B 2 Figure B 2 Main Harness Ulysses and Lightning Main Harness Ulysses and Lightning ...
Page 234: ...Figure B 3 Figure B 3 Main Harness Firebolt Main Harness Firebolt ...
Page 240: ...Figure B 6 Figure B 6 Lighting Circuit Firebolt Lighting Circuit Firebolt ...
Page 242: ...Figure B 7 Figure B 7 Component Circuits All Models Component Circuits All Models ...
Page 248: ...Figure B 10 Figure B 10 Starting Circuit Firebolt Starting Circuit Firebolt ...
Page 250: ...Figure B 11 Figure B 11 Charging Circuits All Models Charging Circuits All Models ...
Page 266: ...B 40 2008 Buell XB Diagnostics Appendix B Wiring Diagrams NOTES ...
Page 268: ...NOTES ...
Page 272: ...C 4 2008 Buell XB Diagnostics Appendix C Conversions NOTES ...
Page 273: ...SUBJECT PAGE NO D 1 GLOSSARY D 1 APPENDIX D GLOSSARY ...
Page 274: ...NOTES ...
Page 278: ...D 4 2008 Buell XB Diagnostics Appendix D Glossary NOTES ...
Page 282: ...IV TOOLS NOTES ...
Page 284: ...VI TORQUE VALUES NOTES ...
Page 287: ...INSIDE BACK COVER GOES HERE ...
Page 288: ...OUTSIDE BACK COVER GOES HERE ...