An engine analyzer stores acquired cylinder waveform data in circular
buffers respectively associated with the cylinders in accordance with
cylinder selection by the user, with each buffer including a plurality of
storage cells respectively storing data for individual firing cycles of
the associated cylinder, and simultaneously displays the waveform for a,
single selected cylinder on one trace of a display screen and waveforms
for all cylinders for which data is stored on a second trace, so that data
can be acquired and displayed from direct ignition engines with the use of
a single pickup lead connected to selected cylinders one cylinder at a
time. Various display modes are possible, including a frozen mode in which
all stored waveform data may be reviewed and displayed.