I read an article about it fee years ago. It was about all these additives and aftermarket kits to increase your mileage. Most of these are bogus or don't show results as advertised.
The fact is that just by changing your driving habits . You can get better mileage rather than using these so called pills. Avoid jerky starts. not making Engine roar at idling or while driving by pressing accelerator for no reason, keeping tires properly inflated, proper required engine maintenance, proper oil changes plus air filter and so on.
EPA has tested hundreds of such products and did extensive testing and not a single one came put to be true as advertised.
I m not an expert but as I read on various automotive blogs and These additives or pills are useless..
https://www.pakwheels.com/forums/members-member-rides/215631-pakwheelers-map-place-marker-get-connected
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