Customer Ratings & Reviews

Started using P.I. Additive about two years ago because where I live in Missouri we use 10% enthanol in our gas and now because of the fuel prices last year it is now up to 15% so I like to make sure my cars fuel systems are treated every 6K mile. I just treated my 2014 F150 that is flex fuel capable and have notice my fuel mileage has picked up 1-2 MPG since the last treatment. I trust Amsoil products and am now using them exclusively in all my autos.

I only use the best for my Civic Type R and Amsoil is the best! Fast shipping great prices 10/10 I recommend them to everyone!

I have used P. I. for many years. I even give a bottle to friends, ever now and then.. We all love it...

In my past 5 family vehicles in Upstate New York, this additive has helped them start esp in very cold snowy winters, while correcting some of the damage caused by Ethanol-Added gasoline. This is the only gasoline additive I use.

trying to do what I can to help keep the carbon buildup to a minimum.

Have used Amsoil PI in past. First time in our new 2022 TRAIL BOSS LTD 2.7T 4 CYLINDER using E15 that is rated 86 octane average. It has 24000 miles on it and the PI is noticeably improving the burn. I am retired tribologist from a major OEM and did chem testing of fuels and lubricants for 45 years. Most additives don't work nor will they mix properly cold and via gravity or splash. Amsoil knocked this chemistry out of the park. Smoother idle, cleaner tail pipe and using crappy high altitude E15 fuels my MPG is up. Will and do use oil analysis from SYNTHETIC ADVANTAGE ISO CERTIFIED OIL ANALYSIS to confirm.

The best gas additive I have ever ordered.

Used to clean my Injectors. Zero issues

Used this in my car to clean system. Very good product.

So far so good very happy

Highly recommended

Excellent product. Highly recommended.

Keeps engine running smoothly

Used in high mileage (214,000+) Camry that had become sluggish. Noticed added pep to vehicle.

Great product, but if you ship it from Minneapolis again and I have to pay Minneapolis taxes, I’ll send it back. Don’t do it again

This additive replaces the Seafoam I used to use in my personal fleet to keep everything clean and well running, all very good as far as I am concerned.

worked good car ran better

I only ran this stuff one time so I honestly can’t say if it does what it claims but it seemed to work pretty well. I would have to run it at least a few more times and average my mpg to say for sure one way or the other.

This stuff works as stated one tank and what a difference!

I noticed immediately the increase in performance