4-38 2007 Buell Lightning: Fuel System
HOME
MISFIRE 4.15
GENERAL
Misfire At Idle or Under Load
Misfire conditions may be caused by:
● Battery condition and connections.
● Fuel system problems. See tables under 4.8 INITIAL
DIAGNOSTIC CHECK.
DIAGNOSTICS
Diagnostic Notes
The reference numbers below correlate with the circled num-
bers on the Test 4.15 flow charts.
1WARNING1WARNING
Thoroughly wipe up any spilled fuel and dispose of rags
in a suitable manner. Any open spark around gasoline or
other combustibles could result in fire or explosion caus-
ing death or serious injury.
1. See Figure 4-30. A SPARK TESTER (Part No. HD-
26792) must be used to verify adequate secondary volt-
age (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 cylin-
der head bolt.
d. While cranking engine, watch for spark to jump
tester gap on leads.
e. Reinstall and repeat procedure on other spark plug
cable.
2. Perform spark plug cable resistance test.
a. Remove spark plug cable from spark plug and igni-
tion coil. See 7.4 SPARK PLUG CABLES.
b. Using an ohmmeter, touch probes to terminals on
each end plug wire.
c. Compare resistance values to Table 4-16. 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 coil damage. See 4.32 IGNITION COIL.
4. This test can also be performed by substituting a known
good coil for one causing the no spark condition. The coil
does not require full installation to be functional. Verify
faulty coil by performing resistance test. See 4.32 IGNI-
TION COIL.
5. Use HARNESS CONNECTOR TEST KIT (Part No. HD-
41404) gray pin probe and patch cord.
Figure 4-30. Spark Tester (Part No, HD-26792)
Table 4-16. Spark Plug Cables
SPECIFICATION FRONT & REAR
Length - in. (mm)
5.75 in.
(146mm)
Resistance - ohms 1,430 - 3,360
b0565x4x
To Next Page
Loading...
Need help?
General
