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When the vehicle died, it can be seen that the injector current pulses disappeared. However, we still have D-ref pulse and primary ignition trigger. Now, let's review system operation to think this problem out.

1. The ignition module uses the 7 tooth magnetic CKP sensor to sync coil firing.
2. The ignition module processes the CKP sensor signal through an A/D converter.
3. The module then sends the digital signal to the ECM for a tach signal, ignition and injector firing.

By looking at the above patterns we can deduct that the CKP sensor and the ignition module are doing their jobs. The missing piece of the puzzle is injector firing. The ECM has the information available to fire the injectors, however, the pulse disappeared. Logical deduction leads us to a faulty ECM.

Note:

The patterns from this vehicle were recorded with the Omitec PDA. The odds of finding a problem like this without record capabilities are tremendously reduced. When planning an equipment purchase, keep this feature in mind.