Capacitor discharge ignition analyzer includes a pulse source operable to generate electrical signals related to the input-output signals of various capacitor discharge ignition systems including battery driven and alternator driven systems. The analyzer includes an electronic circuit generating an output signal approximating that of the permanent magnet alternators for charging of alternator driven systems and a circuit to generate a trigger pulse. The output of the capacitor is connected to a spark gap unit having an outer enclosure with a small opening. This permits direct testing of the ignition system on the engine without any practical danger of generating explosions as a result of surrounding gas fumes.