As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AFTER PUSHBACK #1 ENGINE WOULD NOT START WITH IGNITION IN "IGN R" POSITION. GROUNDED - YES. REMOVED AND REPLACED R/H IGNITOR PLUG REF B737-900 AMM 74-21-02. REMOVED AND REPLACED R/H IGNITION LEAD REF AMM 74-21-01. PERFORMED IGNITION SYSTEM AUDIBLE TEST, BOTH L/H AND R/H OPS CHECKS GOOD. NO DEFECTS NOTED.