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AMSOIL P.i.® Performance Improver Gasoline Additive
Product code : APICN-EA
AMSOIL P.i.® Performance Improver Gasoline Additive
Product code : APICN-EA
Current price:
$18.99
Retail Price
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Estimated delivery by Tue, Jul 7
to Columbus - 43215.
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- 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. -
We offer easy returns for customers. If your product is unused and unopened, you may return it within 30 days for a full refund of the purchase price. View full AMSOIL Return Policy.
-
We accept Visa, Mastercard, American Express, Discover and PayPal, and provide secure checkout and encrypted payment processing.
About this item
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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]( "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.
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star rating
Great productBy FRANK, a Verified Buyer on July 01, 2026I very rarely leave product reviews, but this one deserves a review. I have 4 vehicles (mine, my wife's, and both of our kids), and 3 of them were bought as used vehicles. So far, I have run 2 bottles through each of the vehicles, and I have noticed a marked improvement in idling, acceleration and gas mileage. My younger son's vehicle had the best improvement. He has a 2018 Subaru, and after 2 bottles of Amsoil he went from getting 18 mpg in the city to getting 22 to 23 mpg in the city, along with much better acceleration and smoother idling. It was getting about 21 to 22 mpg on the highway, but I haven't tested that yet since using Amsoil, although I'm positive it'll be much better now. Additionally, I used 1 bottle, so far, in my mom's 21 year old truck. It idles much better and accelerates much faster and smoother than before. I haven't calculated the gas mileage usage yet, but I'm sure it's better as well. For the past 36 years, I used 2 other very well known fuel additives every oil change, and I did quite a bit of research before buying Amsoil. After the improvements I've seen in 5 different vehicles ranging from 2005 to 2026 year models...I will ONLY use Amsoil every oil change.Bottom LineYes, I would recommend this to a friend.Was this review helpful?
-
star rating
Amsoil P.iBy MICHAEL, a Verified Buyer from Michigan on June 30, 2026Nice product! Its works!Bottom LineYes, I would recommend this to a friend.Was this review helpful?
-
star rating
Awesome.By JONATHAN, a Verified Buyer from East tawas on June 23, 2026Went from maybe 17 mpg to 18.5 after using this product.Bottom LineYes, I would recommend this to a friend.Was this review helpful?
-
star rating
Engine fuel cleanerBy ANTHONY, a Verified Buyer from Alberta on June 22, 2026Applied the Amzoil Gasoline PI to a 2015 Subaru Forrester 2.0L Turbo, and after one tank noted a smoother idle and what feels like an increase in power. Very pleased with the product.Bottom LineYes, I would recommend this to a friend.Was this review helpful?
-
star rating
Highly recommendedBy Doc, a Verified Buyer from Brighton, MI on June 22, 2026This great product also does an amazing job of keeping the ports clean and will prevent the buildup of residue in the engine!Bottom LineYes, I would recommend this to a friend.Was this review helpful?
-
star rating
Great productBy TODD, a Verified Buyer on June 16, 2026I use P.I. In all of my gas powered equipment. Seems to really work well with keeping things clean and stable.Bottom LineYes, I would recommend this to a friend.Was this review helpful?
-
star rating
Good gas additiveBy ALFRED, a Verified Buyer from Plano, TX on June 16, 2026With the worsening quality of fuels getting delivered these days, to keep your fuel system running clean, and prolong your engine life, use this!Bottom LineYes, I would recommend this to a friend.Was this review helpful?
-
star rating
Amsoil gasoline additiveBy MELVIN, a Verified Buyer from Fort Macleod Alberta on June 10, 2026Great product have had zero fuel issuesBottom LineYes, I would recommend this to a friend.Was this review helpful?
-
star rating
Fuel additiveBy WILSHIRE, a Verified Buyer on June 08, 2026Great productBottom LineYes, I would recommend this to a friend.Was this review helpful?
-
star rating
Added fuel system protectionBy PHILIP, a Verified Buyer from South Carolina on June 08, 2026I use it once a year. My garage queen sits for extended periods and this product protects and cleans my fuel system for optimal pergormanceBottom LineYes, I would recommend this to a friend.Was this review helpful?
-
star rating
WARRANTY-
- 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. -
We offer easy returns for customers. If your product is unused and unopened, you may return it within 30 days for a full refund of the purchase price. View full AMSOIL Return Policy.
-
We accept Visa, Mastercard, American Express, Discover and PayPal, and provide secure checkout and encrypted payment processing.
-
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]( "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.
-
-
-
star rating
Great productBy FRANK, a Verified Buyer on July 01, 2026I very rarely leave product reviews, but this one deserves a review. I have 4 vehicles (mine, my wife's, and both of our kids), and 3 of them were bought as used vehicles. So far, I have run 2 bottles through each of the vehicles, and I have noticed a marked improvement in idling, acceleration and gas mileage. My younger son's vehicle had the best improvement. He has a 2018 Subaru, and after 2 bottles of Amsoil he went from getting 18 mpg in the city to getting 22 to 23 mpg in the city, along with much better acceleration and smoother idling. It was getting about 21 to 22 mpg on the highway, but I haven't tested that yet since using Amsoil, although I'm positive it'll be much better now. Additionally, I used 1 bottle, so far, in my mom's 21 year old truck. It idles much better and accelerates much faster and smoother than before. I haven't calculated the gas mileage usage yet, but I'm sure it's better as well. For the past 36 years, I used 2 other very well known fuel additives every oil change, and I did quite a bit of research before buying Amsoil. After the improvements I've seen in 5 different vehicles ranging from 2005 to 2026 year models...I will ONLY use Amsoil every oil change.Bottom LineYes, I would recommend this to a friend.Was this review helpful?
-
star rating
Amsoil P.iBy MICHAEL, a Verified Buyer from Michigan on June 30, 2026Nice product! Its works!Bottom LineYes, I would recommend this to a friend.Was this review helpful?
-
star rating
Awesome.By JONATHAN, a Verified Buyer from East tawas on June 23, 2026Went from maybe 17 mpg to 18.5 after using this product.Bottom LineYes, I would recommend this to a friend.Was this review helpful?
-
star rating
Engine fuel cleanerBy ANTHONY, a Verified Buyer from Alberta on June 22, 2026Applied the Amzoil Gasoline PI to a 2015 Subaru Forrester 2.0L Turbo, and after one tank noted a smoother idle and what feels like an increase in power. Very pleased with the product.Bottom LineYes, I would recommend this to a friend.Was this review helpful?
-
star rating
Highly recommendedBy Doc, a Verified Buyer from Brighton, MI on June 22, 2026This great product also does an amazing job of keeping the ports clean and will prevent the buildup of residue in the engine!Bottom LineYes, I would recommend this to a friend.Was this review helpful?
-
star rating
Great productBy TODD, a Verified Buyer on June 16, 2026I use P.I. In all of my gas powered equipment. Seems to really work well with keeping things clean and stable.Bottom LineYes, I would recommend this to a friend.Was this review helpful?
-
star rating
Good gas additiveBy ALFRED, a Verified Buyer from Plano, TX on June 16, 2026With the worsening quality of fuels getting delivered these days, to keep your fuel system running clean, and prolong your engine life, use this!Bottom LineYes, I would recommend this to a friend.Was this review helpful?
-
star rating
Amsoil gasoline additiveBy MELVIN, a Verified Buyer from Fort Macleod Alberta on June 10, 2026Great product have had zero fuel issuesBottom LineYes, I would recommend this to a friend.Was this review helpful?
-
star rating
Fuel additiveBy WILSHIRE, a Verified Buyer on June 08, 2026Great productBottom LineYes, I would recommend this to a friend.Was this review helpful?
-
star rating
Added fuel system protectionBy PHILIP, a Verified Buyer from South Carolina on June 08, 2026I use it once a year. My garage queen sits for extended periods and this product protects and cleans my fuel system for optimal pergormanceBottom LineYes, I would recommend this to a friend.Was this review helpful?
-
star rating
