Customer Ratings & Reviews

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!!!

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.

I started using PI when I bought my 2001 GMC that has an 8.1l engine. I does help to improve the gas mileage on my truck. The 8.1 was not built for mileage but for towing. PI does improve the gas mileage. I highly recomend this product.

As with all AMSOIL treatments, this one is no different - it's a must-have for any gas automobile. I use one bottle in my Grand Marquis every 3-4000 miles and my mpg's stay between 19-20 in town (which is 2-3 mpg above the EPA's average estimate for the little 4.6L). 28-30mpg on the highway at 70mph. YEAH. Of course, every fluid in my car is AMSOIL, from differential to engine oil to coolant. I run Sig series 5W-20 with an EA011 filter every 10,000 and I use a WIX 46814 air filter (nothing special in terms of air flow). I also have a coolant filter with the Donaldson P554685 filter running AMSOIL HD coolant. With all of the positives of my AMSOIL-fan-boy tendencies, it really is the best stuff on the market for keeping your engine in tip-top shape. But buyer beware, if you're going to use any fuel treatment from AMSOIL (including the diesel treatments, which I use on my 6.0 - which also runs like a top), have a Swiss Army knife to help you open the lid. The child safety mechanism doesn't work and it's impossible to open the lids without either cutting the lid off or using a pair of channel locks to vise it off. And of course, there is a foil tab underneath the lid that is also very hit-and-miss. I've found that out of a case of 12 (of any fuel treatment), at least 3 of the safety tabs under the lid are defective. They either leak in the box (wasting the precious fuel treatment) or are impossible to remove without a tool (which is counter to the pull-tab design).

Great fuel additive if you are looking to keep your motor clean and running at its peak. This is the fuel additive you need.

Amsoil does it again with a great product and ease of use

This stuff is great! I used to use Marvel's in my oil and in every tank of gas, but my Suburban was starting to slow itself down, the knock sensors were crying all day... I switched to Amsoil and things are looking up! I use Signature series oil and add this PI every 4th tank; no more knock. Very pleased!

I never really believed the effects of these gasoline additives, but this one produced results. My truck doesn’t have that thick white exhaust smoke any more and starts way better than it did before two applications of the performance improver. You do need multiple applications to see any improvement, but my truck only took two.