GM Optispark — Faulty Ignition Timing - Low Res Signal
This vehicle was towed in after the customer replace the Optispark distributor with a remanufactured unit. An in-cylinder pressure test was performed and compared to the low resolution, high resolution and secondary spark for #2 cylinder. As the image shows, the optispark unit is out of time.
Here is a capture of the repaired vehicle.
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