Jury is out on whether this product is effective. I add a bottle when I change the oil in our cars each year, and we generally only put about 5-6k miles on our cars each year, so it's close to the recommended 4k miles. Been using this product for about two years and all the cars run well, so that's a good sign.
I drive a bored and stroked Hemi (gaoline powered) Ram truck with 11.0:1 compression. It boils fuel in the rails when idling in warm weather. Good gas is a necessity but hard to find and not cheep. I'm retired and it may take me 2 weeks, or more, to burn a tank full. Amsoil PI seems to work better than Lucas as measured by my throttle experience :]
93 pump gas stays fresh for weeks and throttle response is always crisp and powerful. It "seems" to increase the boiling point of fuel as my soggy throttle response in traffic is not as bad.
I put PI in every fill up of both my V8 powered vehicles. It truly is, as the label implies, a performance improver!
Amsoil just makes the best stuff period. Thanks Amsoil!
HAVE USED P1 FOR A NUMBER OF YEARS AND IT WORKS VERY WELL TO KEEP CARS RUNNING AT OPTIMUM PERFORMANCE.
Bottom Line
Yes, I would recommend this to a friend.
Was this review helpful?
5 star rating
Gas Additive a plus
By 
JW, 
a 
Verified Buyer 
from 
Post, Texas 
on 
October 19, 2021
I run the gasoline additive approximately every 90-100 days in both my wife's 2020 Ford Explorer, and in my old '95 Ford F-150. never any problems with either vehicle. Especially seems to keep my old truck running well.
I’ve use P.i. Performance Improver for first treatment in two vehicles, both with original internals, injectors, etc. 1995 Tacoma (2.7 L) with over 300K miles, and 1998 Wrangler (4.0 L) with over 150K miles. Both have smoother idle, enough performance improvement to notice, and gained an extra mile per gallon. Will continue use at recommended interval.
This is a carousel of Shop by Equipment slides. Use Tab to navigate through the carousel or the Next and Previous buttons. Use Enter to select a slide.
Thank you for visiting www.amsoil.com. Certain parts of this website may not function with Internet Explorer. To continue shopping with us, please update your browser using one of the options below.