Customer Ratings & Reviews

I use this in all of my cars at each oil change and at the halfway point to the next oil change. I use this treatment when I work on friends cars and they always say that their car has a lot of pep and thank me for the great job.

No complaints so far, seems to allow my cars to run a bit smoother after using!

Have been using the P.I. Improver since AMSOIL stated making it. Have used other AMSOIL in everything I can get it in since 1983.

PI improver really gave my Audi A4 more pep right off the bat.

Used Lucy’s gas treatments in past but this was noticeably better. Felt like I had more HP

This additive make my car a monster

Seems to work fuel mileage did go up

I have been an Amsoil wholesaler for many years now and hands down this is by far the most superior product you can buy and install in your vehicles. I use all amsoil products and have never had any failures whatsoever !

By far this is the best fuel injector cleaner and fuel system cleaner as well.

I have a high performance engine that is a real gas-aholic. She is a heavy drinker, so any improvement in gas mileage is much appreciated. I've only used it once for the first time and I already have a 3 tenths per gallon increase in gas mileage. That is a 10% increase in gas mileage for my heavy drinker.

This stuff just works. Promises a difference in just one tank and as promised it works- more horse power and smoother running engine

My 2,0 ford runs direct injection, puts the injectors inside the combustion chamber where carbon can be a problem. P.I. performance Improver really keeps injectors, valves, and piston tops clean. Works Great

As the title states and works as it should. I use it with the upper cylinder lube and have better throttle response and a little better gas mileage improvement.

Great addictive. Keeps injectors functioning well

Super augment la performance qui est quand même remarquable

Works great and increases mileage

This is a great product. I drive some really old cars, including my lovely 1988 Cadillac Sedan de Ville, and you can just imagine what kind of crud has been building up in those fuel tanks. P.I. helps get rid of the stuff as well as clean out the fuel injectors so that you will get good ignition. You only need to use P.I. every four thousand miles or so, although I recommend that you start out with a more frequent interval. As the price of gasoline has increased drastically, the expense of Amsoil's fuel additives has become less and less of an issue. These additives are well worth it.

I use this at every oil change.

Been using P.I. in my vehicles for a while, and I love that the new bottle is designed to fit in the cap-less fuel fillers on newer vehicles without having to find the funnel they include for emergency fuel-ups. Way ahead of the competition, and a great product inside to boot!

Noticeable gains when using this product, especially off the line.