AMP EFI MS3Pro - Trigger Logger; Composite Logger; Sync Error Logger

8.4 Tooth / trigger logger and troubleshooting RPM issues 8 TROUBLESHOOTING AND DATA LOGGING
8.4.4 Trigger logger
This records the "decoded" and filtered tach events and is one pulse per normal ignition event. Since trigger
logging is after the wheel decoding, this information is not very useful for diagnosing most sensor faults. It is only
useful in spark modes that use an external device for wheel decoding, such as EDIS.
8.4.5 Composite logger
The basic tooth logger records enough information to analyze a typical missing tooth wheel on the crank. However,
if the engine uses both cam and crank sensors, then a new logging method is required. This third composite logger
records both crank and cam signals and under some circumstances it will record both edges of the input signal. It
could be used as a crude two channel oscilloscope. The composite logger shows three signals.
• The green line at the top represents the cam signal.
• The blue line in the middle represents the crank signal.
• The red line at the bottom represents error pulses that do not fit the expected pattern.
This log shows Subaru 6/7. This is a single edged signal, so the visualization can only show a point/line.
This log shows an example double edged signal with some noise.
Here is a screen shot of a simulated signal with a 24 tooth crank wheel and a 1 tooth cam wheel. The crank
signal is single edged and the cam signal is double edged.
8.4.6 Sync error logger
This is a variant of the composite logger. During normal engine operation it will show nothing at all, but if a sync-
loss event occurs (due to noise) it shows the tooth pattern that led up to the loss of synchronization. This allows
you to pinpoint the problem without searching for the needle in the haystack as would be the case trawling through
AMP EFI MS3Pro manual version 1.202, firmware 1.5.0, 4/21/2017 Page 295