Customer Ratings & Reviews

2006 Camaro V6 had firing issues and various engine codes had came up. After 1 treatment of PI Performance Improver followed up with 2 back to back treatments of the Amsoil Gasoline Additive upper cylinder lubricant the car now has no firing issues and no codes. I highly recommend the product at every oil change followed up with a couple treatments of the upper cylinder lube. For good measure keep the external fuel filter changed at every other oil change. All of this process I've completed as well in my 1999 K2500 with the old spider fuel injection on its 350 sbc. This stuff simply works.

Used as recommended for many years in both GDI & non-GDI vehicles for 200K+ miles. No issues with fuel injectors or Intake valve buildup.

Love it you really feel the difference

Your car feel thank you using this product!

Removes all the impurities from the gas.Vehicle runs smoother.

Great FI cleaner. Cleans combustion chambers and keeps your vehicle running new.

I use this in my 2013 2500 HD GMC and have had no fuel related problems in 160,000 miles.

I am always a little apprehensive about performance claims on things you cannot physically see or test for. This product defies that... I decided to switch to Amsoil everything on our 2015 GMC Acadia and said what the heck I’ll try this out too. After using it once my 3-4 crank start ups went back to the factory fresh 1-1/2. Went on a family trip that usually uses 1-1/2 to 1-3/4 of a tank and this is where it got really good, went round trip on 1 tank!!! Highly recommended this, can’t say the frequency, but at least once a year. Good stuff!!!

Haven't used this product long enough to give it a honest review, but if it is as good as the other Amsoil products then its a good product.

Love this product. Within a day can feel the improvement in power. Makes my Durango R/T roar.

Very pleased with results

Good stuff for the keeping the fuel system fairly clean. I use it about twice a year, or every 4k miles on all my vehicles.

ALL AmsOil products are excellent, better than any comparable brands 👍🏻💪

Works great.

I have been using this product for years, keeps the fuel system in our 2015 Prius V and 2013 Lexus CT200H in excellent condition. Both cars average 40 to 43 MPG consistently, around town and interstate driving. I highly recommend this product to all who are serious about keeping their cars in top performance condition. I go above and beyond Amsoil's recommended usage, I add one half a bottle every other month to keep the fuel system clean and in top performance.

I highly recommend. Though I'm not sure how clean it makes things in the engine, I can tell you for sure that you notice something from the first bottle you put in. I use a bottle of this at the first fill up after each oil change.