1986-1987 Honda TRX350 FourTrax 4X4, 1987-1989 TRX350D Foreman 4X4 Service Manual, Page 253Get this manual
IGNITION SYSTEM
TROUBLESHOOT ING
Weak or no spark at plug 1Try spark test with known good spark plugWEAK OR NO SPARK 2Check spark plug wire for loose or poor contact at the spark plug cap, then try spark test againWEAK OR NO SPARK 3Check CDI unit connectors for loose or poor contact NORMAL 4Check the resistance, continuity and voltage at the CDI unit connectors of the wire harness side (page 17-4)Also check ignition secondary coil resistance (page 17-5)ALL NORMAL ABNORMALGOOD SPARK
Faulty spark plug
GOOD SPARK
Loose or poor contact of spark plug cap
ABNORMAL
Loose or poor contact of COl unit connectors