I dont see how that would put out a gas fire on an engine?
it will, by displacing the oxigen,...
...provided fire has developed until a certain limit, otherwise no chance of controlling the fire, you know that depending on fire spread not even to firebrigades (that will eventually let the car burn to ashes))
chek other you tube videos to see various tests by norwegian firebrigades, including oil filter cartridge burning inside the engine compartment,
in the same conditions of fire development this is much better than conventional fire extinguishers for the reasons i pointed out before, works in the 100% of the cases, duration is 50 seconds, and leaves no residue
this is the best alternative to conventional dust fire extinguishers that is the only kind usually available (i know that you have halon ones, that are strictly forbidden in Europe, so i will not judge those ones, but even halon ones are heavy, and this only weighs 250 grams)
we can use CO2 ones, that leave no residue, but they are very heavy and they throw subzero temp CO2 gas onto the engine
so yes this is a good solution