From your screen name Iím guessing you live in Tahiti or whereabouts.
I looked up Heet and it appears to be a gasoline antifreeze that combines methanol with water in your tank that then sinks to the bottom and hopefully bothers no one.
Your concern is probably water in fuel from sketchy suppliers and in fact, if water reaches our injectors, it acts like an effective plasma cutter, so you ask a good question.
Fortunately, GM engineers anticipated the problem and if you use AC Delco, coalescing filters in an OEM fuel supply system, water will be removed from fuel by the filter and may later be drained from the bottom of the filter using the provided valve. There is also a float switch connected to the separator for a warning light, but consensus here seems to be if that light comes on, it may be too late and many owners, especially those with lift pumps or filters from other sources (Cat comes to mind) donít worry about water in their fuel.
Frankly, I donít think thatís prudent and I retain the OEM system, although a cracked filter head a few years back prompted purchase of the much less $$$ LLY head.
Many years ago, in the mountains of Central PA, my 1980 Audi diesel would not start at sub-zero temps and with the help of a friendly service tech, I learned there was a metal screen atop the tank which became cold enough to collect and freeze water. Pulled the back seat, found the screen and problem solved. Mechanical Bosch injection in those days @ maybe 5,000 psi (?).
Bottom line, if you have an OEM fuel system, pass on Heet, watch your source of fuel (no crank tanks on pickups!) and check the water drain valve regularly.