What wasn't stated in the wiki was GM had some interesting issues with the HEI at first. The vehicles with them would mysteriously die going down the road but start right back up.
Took them a while to figure out the issue with it since there was no mechanical or electrical reason for it to happen.
What I was told by an instructor was that the engineers that designed the module used a specific frequency for reliability. Turned out that it was basically the same as an 11 meter radio (cb) and when a trucker would key up near one of the units it would die but start right back up again.
