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AMSOIL P.i.® Performance Improver Gasoline Additive

Product code : APICN-EA

  • Restores up to 14% horsepower1
  • Restores GDI fuel injectors to 100% flow rate after one tank of fuel2
  • Improves fuel economy
  • Reduces need for costly higher-octane fuel
  • Helps prevent carbon rap
  • Controls pre-ignition knock
  • Compatible with capless fuel systems

1Based on third-party testing in a 2016 Chevrolet* Silverado* 1500, 5.3L V-8 GDI with 100,616 miles, using one tank treated with AMSOIL P.i. Actual results may vary.
2ASTM D5598(M) – 2013 Buick Regal test vehicle.

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AMSOIL P.i.® Performance Improver Gasoline Additive



AMSOIL P.i. is a potent gasoline performance improver with concentrated detergent that aggressively cleans stubborn, power-robbing deposits from injectors, valves and the combustion chamber. Effective in port and direct injection systems. Bottle compatible with capless fuel systems. Cleans entire fuel system in one tank of gasoline. For use with cars and trucks. Treats up to 30 gallons. Add entire bottle to tank at fill-up. For best results, clean your fuel system with P.i. every 4,000 miles (6,400 km). Do not use with diesel or two-stroke engines.

See the Product Data Bulletin for full details.

MAXIMUM DEPOSIT CLEAN-UP

  • Helps keep valves clean and moving freely.
  • Aggressive additives attack the most common forms of engine deposits and limit their effects.

REMOVES FUEL-INJECTOR DEPOSITS

  • P.i. removes deposits and keeps injectors functioning as they should.
  • Testing shows P.i. restored GDI fuel injectors to a 100% flow rate after one tank of fuel.2

RESTORES HORSEPOWER

  • Third-party testing demonstrated performance of P.i. using a 2016 Chevrolet* Silverado* with 100,616 miles on the odometer.
  • Following a single treatment with P.i., the truck measured an incredible 14% improvement in horsepower.1

Horsepower Comparison

CLEANS COMBUSTION CHAMBER DEPOSITS

  • Fights combustion chamber deposits to help restore power, control knock, increase fuel economy and reduce the need for higher-octane fuels.
  • Protects against compression loss, difficulty starting and rough idling.
  • Reduces possibility of "carbon rap," when deposit buildup causes the piston to hit the cylinder head.
  • Decreases the possibility of pre-ignition "knock" or "pinging."

CAPLESS-COMPATIBLE BOTTLE

  • Bottle is fully compatible with capless fuel systems.

1Based on third-party testing in a 2016 Chevrolet* Silverado* 1500, 5.3L V-8 GDI with 100,616 miles, using one tank treated with AMSOIL P.i. Actual results may vary. 2ASTM D5598(M)-2013 Buick Regal test vehicle.

See the Product Data Bulletin for full details.

AMSOIL P.i.® Performance Improver Gasoline Additive

Warranty

Data Bulletin

SDS



AMSOIL P.i.® Performance Improver Gasoline Additive

  • 5 star rating
    Makes a great gift
    By  SCOTT,  a  Verified Buyer  on  February 07, 2025
    Been using it for a while and it works great been consistently getting better results with it used as recommended super fast shipping and easy to use
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Works as advertised
    By  DAVID,  a  Verified Buyer  from  Colorado   on  February 05, 2025
    Works well. Keeps the fuel system clean.
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Great product
    By  JAMES,  a  Verified Buyer  from  Kirwin, ks  on  February 04, 2025
    Used it, very impressed
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?
  • 5 star rating
    Great products
    By  MICHAEL,  a  Verified Buyer  from  Iowa  on  January 29, 2025
    I have been using this is my 1/2 ton farm truck and wife's 16 Tahoe. It really cleans and have noticed it neutralizing the fuel. My fuel trims and changed and a big notice in my alcohol content is way better. I have also noticed we do not have to complete intake cleanings near as often. Helping with carbon build up. We have noticed a slightly better fuel milage. This has slowed the demand for "fuel tank evap as well". Again, THANK YOU AMSOIL.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Most trusted name in automotive lubricants
    By  MICHAEL,  a  Verified Buyer  from  Oklahoma  on  January 26, 2025
    Love all the Amsoil products
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Superior product
    By  PG,  a  Verified Buyer  from  San Antonio  on  January 26, 2025
    I've used PI for almost a decade now and as far as I'm concerned, its one of the best products AMSOIL makes. While I use it with my cars - and if you start using it early in a car's life, it's going to help keep it from having fuel injector problems - I also use it with small engines. I have a 30AMP generator that wouldn't start at all. I had used fuel with ethanol in it before I became aware that could cause issues. After multiple attempts to start the thing, including using Power Foam in the carburetor, no dice. I figured I'd have to take it to a shop for repairs, but I decided to put in PI with some ethanol free gas and amazingly, that generator cranked up. Shut it off and started it again the next day, no problems starting. Put a half bottle of PI in there with non-ethanol gas and it ran until it was out of fuel. That was 7 years ago, and that generator hasn't given me an ounce of problems starting/running since, including during the Texas deep freeze of 2021 when we lost power for 3 days in sub-20 degree weather. It ran for ~ 55 hours pretty much nonstop. Not going to say PI is magic or a cure for bad maintenance/operation but it worked for me.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great Product
    By  DION,  a  Verified Buyer  on  January 21, 2025
    Great product running it in all of my vehicles. Noticed a big difference in the performance of my vehicles. Used to use a different product, now I'm team Amsoil for sure.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Happy with purchase
    By  RICHARD,  a  Verified Buyer  from  Texas  on  January 18, 2025
    I can see a difference after using
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    It works !
    By  KEVIN,  a  Verified Buyer  from  NH  on  January 11, 2025
    I’ve been using Performance Improver for years, currently my 22’ Toyota & 2013 Honda. Improves gas mileage & gives you an engine boost.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great product
    By  ANDRES,  a  Verified Buyer  from  Toronto   on  January 11, 2025
    I have using it for a while , it does the job
    Bottom Line
    Yes, I would recommend this to a friend.
    Was this review helpful?