AEM 30-6101 Series 2 Plug & Play EMS - Manual (Page 5)

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This product is legal in California for racing vehicles only and should never be used on public highways.
6) Troubleshooting an engine that will not start
a) Double-
check all the basics first… engines need air, fuel, compression, and a correctly-
timed spark event. If any of these are lacking, we suggest checking simple things first.
Depending on the symptoms, it may be best to inspect fuses, sufficient battery voltage,
properly mated wiring connectors, spark using a timing light or by removing the spark
plug, wiring continuity tests, measure ECU pinout voltages, replace recently-added or
untested components with known-good spares. Check that all EMS sensor inputs
measure realistic temperature and/or pressure values.
b) If the EMS is not firing the coils or injectors at all, open the Start tab and look for the
‘Stat Sync’d’ channel to turn ON when cranking. This indicates that the EMS has
detec
ted the expected cam and crank signals; if Stat Sync’d does not turn on, monitor
the Crank Tooth Period and T2PER channels which indicate the time between pulses
on the Crank and T2 (Cam) signals. Both of these channels should respond when the
engine is cranking, if either signal is not being detected or measuring an incorrect
number of pulses per engine cycle the EMS will not fire the coils or injectors.
c) If the Engine Load changes when the throttle is pressed this usually indicates that there
is a problem with the MAP sensor wiring or software calibration (when the EMS detects
that the MAP Volts are above or below the min/max limits it will run in a failsafe mode
using the TPS-to-Load table to generate an artificial Engine Load signal using the
Throttle input). This may allow the engine to sputter or start but not continue running
properly.