Does fuel additives or something similar like that really works?
 

Hello everyone I would like to ask whether or not fuel additives from STP, caltex etc really works to improve fuel consumption?

Welcome. I tried a few tankfuls adding Redex Petrol Treatment. Didn't notice any improvement in fuel efficiency.

Depends what kind you use, an octane booster should have the same effect as using premium fuel as you're just increasing the octane number. I know some people who use an additive every tankful of diesel just to keep the injectors from clogging up, but octane boosters are different.

The octane boosters only lift the value by a little amount per bottle. If you want higher octane, just get the higher octane fuel.

If your fuel system is gunked up, you might see an improvement if the additive cleans it up. Otherwise, they aren't going to help any more than a quality gasoline.

In truth, ethanol is an additive to 84 octane 100% gasoline(E0), making 87 octane, E10. Since, E0, in my last five low compression ratio, 87 octane engined cars, gave 8% ,8%, 7%-8%, 7% & 6% better MPG, ethanol isn't functioning properly. Also, some vehicles, burning E0, gave excellent emissions tests.

I use Techron on my truck and it works great. I get 2-3 more MPG's.

years ago I used a fuel additive product from amsoil that made a big improvement and it smoothed out my engine and I didn,t have 50,000 on my chev impala.. the cost was up there to where I didn,t think it was cost effective tho !!!!

I keep meticulous and accurate fuel economy readings. Here's a graph since May 2015 (miles per US gallon). The spikes are hypermiling during long road trips.

Based on the variances I already experience using the same fuel, how could I possibly determine I got a 1-2 MPG increase in fuel economy when adding a fuel additive?

Obviously, in real-world driving, there are other significant variables that affect fuel economy, such as traffic, routes, and weather.

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