J.P. Instruments EDM 930 Primary Pilots Guide - Manual (Page 12)

For Your Safe Flight Page 7
the correct value for EGT difference rich of peak operation at 75%
and 65%
7. You can also see what the peak EGT was by holding the PEAK
button.
8. Tap STEP to exit the Lean Find Mode.
Section 2 - Interpreting Data
Operation for each Phase of Flight
(worth adding to your run-up checklist)
Engine
Run-Up
Suggested setup:

Set engine to run-up RPM
Normalize view:

Manual mode
Verify:

uniform rise of about 50°F in all EGTs in single
magneto operation.

uniform rise of EGTs with application of the mixture
control
.
Be alert for:

unusually low voltage (less than nominal battery
voltage)

cold OIL and normal oil pressure

abnormally high CHT

large drop in EGT on one cylinder in single magneto
operation—may be fouled spark plug.