Engine would crank over at a normal RPM. Spark would occur then stop, (intermittent spark). There was no fuel injector pulse. Spark was tested using an HEI spark tester and injector pulse monitored with a noid light.
Once the faults were confirmed I connected my scan tool. In this case a DRB III. The scan tool confirmed my suspicion, the engine was out of sync. See arrow on photo below.
This video shows what it looks like when cranking the vehicle and viewing the sync data via scan tool data stream.
Next up was checking both cam and crank signals (synchronization) using my ATS lab scope. The pattern below shows an engine that us out of time. The arrow points to a line that depicts (about) where the cam sensor signal (green pattern) should align with the crank signal (yellow pattern)
Aligning the timing mark on the crank pulley and camshaft sprockets was the final test. The timing belt had jumped a few teeth and luckily this engine is not an interference engine. A new timing belt kit and the engine was running normally.
thats amazing that the belt changed teeth and did not have to break to do so. i had just seen a chain type 6 cyl engine that was so loose, the crank could be turned the entire distance the scale reads and beyond before the distributor started to turn. we found it on test ns 1 step 14 without any expensive tester. just a base engine static line up inspection. the sensors had been checked with a fluke 88 and recorded min/ max and an updated ckp was available with larger connector pins. unfortunately the customers incorrect pcm kept us from hearing it run without carb spray. i am sure when he follows your advice about correct parts verification . it should start. he just wont listen and wanted to weasel out on the base engine repair bill