Buell 2002 S3T, Service Manual

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4-40 2002 Buell S3T: Fuel System
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MISFIRE 4.16
GENERAL
Misfire At Idle or Under Load
Misfire conditions may be caused by:
●
Battery condition and connections.
●
Fuel system problems. See tables under 4.9 INITIAL
DIAGNOSTIC CHECK .
DIAGNOSTICS
Diagnostic Notes
The reference numbers below correlate with the circled num-
bers on the Test 4.16 flow charts.
1 1
WARNING
1
WARNING
Any open spark around gasoline or other combustibles
may result in fire or explosion. Thoroughly wipe up an
spilt fuel and dispose of rags in a suitable manner. Fail-
ure to comply could result in death or serious injury.
1. See Figure 4-37. 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. For best results, use a needle nose pliers
for removal/installation on coil. Gently grasp cable
as close to terminals as possible.
b. Using an ohmmeter, touch probes to terminals on
each end plug wire.
c. Compare resistance values to Table 4-12. 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
7.4 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
7.4 IGNI-
TION COIL .
5. Use HARNESS CONNECTOR TEST KIT (Part No. HD-
41404), gray pin probe and patch cord to the coil con-
nector [18].
6. Inspect for corrosion at battery terminals, main circuit
breakers, ignition fuse terminals (GY/O and R/BK), right
handlebar connector [1] and coil connector.
Figure 4-37. Spark Tester
Table 4-12. Spark Plug Cables
SPECIFICATION REAR FRONT
Length in. (mm)
19.0-19.25
(482.6-489.0)
7.25-7.50
(184.2-190.5)
Resistance-ohms 4750-11,230 1812-4375
b0565x4x