Fuel System Treatment · Vyscocity Authorized Dealer
Where to Buy AMSOIL P.I. Performance Improver
AMSOIL P.I. Performance Improver is a concentrated gasoline fuel additive designed to clean fuel injectors, remove combustion deposits and help restore lost performance in modern gasoline engines.
If your engine has a rough idle, lazy throttle response, poor fuel economy or carbon-related performance loss, P.I. is one of the easiest maintenance products to try before assuming something major is wrong.
Purchases complete on AMSOIL.com with Vyscocity dealer code applied. Preferred Customer pricing may be available at checkout.
The Problem
Modern Gasoline Engines Get Dirty Faster Than Most Drivers Realize
AMSOIL P.I. Performance Improver is built around a simple problem: gasoline engines do not stay clean forever. Fuel injectors, intake valves and combustion chambers all operate in harsh conditions. Heat, pressure, short trips, cheap fuel, extended maintenance habits and normal engine operation can all contribute to deposit buildup.
That deposit buildup does not usually happen all at once. It creeps in slowly. The vehicle still starts. It still drives. Nothing feels catastrophic. But over time, the engine can lose some of the crisp throttle response, smooth idle and power it had when it was cleaner.
This is especially true for gasoline direct injection engines, often called GDI engines. In older port fuel injected engines, fuel was sprayed into the intake port and helped wash the intake valves. In a GDI engine, fuel is injected directly into the combustion chamber. That design improves power and efficiency, but it also means the intake valves no longer get the same natural cleaning effect from gasoline.
That is why a modern engine can have carbon-related driveability problems long before it feels worn out. The engine may not need a major repair. It may just need the fuel system and combustion areas cleaned.
Common symptoms of deposit buildup include rough idle, hesitation, lazy acceleration, reduced fuel economy, harder cold starts, elevated emissions and a general feeling that the engine is not as sharp as it used to be. On some vehicles, deposits can also contribute to knock, misfires or fuel-trim problems.
AMSOIL P.I. is designed to attack those deposits during normal driving. You add the treatment to the fuel tank, run the vehicle through the treated gasoline and let the chemistry do the work. It is not a replacement for proper diagnosis, but it is a smart first step when the symptoms point toward fuel system contamination or deposit-related performance loss.
Why It Works
AMSOIL P.I. Targets the Deposits That Steal Performance
Not every fuel additive is aimed at the same job. Some are light maintenance cleaners. Some are fuel stabilizers. Some are octane boosters. AMSOIL P.I. is a concentrated gasoline detergent treatment focused on cleaning deposits that interfere with normal fuel delivery and combustion.
Modern engines are sensitive to small changes in airflow, injector spray pattern and combustion quality. A restricted injector does not need to be completely plugged to cause trouble. A dirty intake valve does not need to be buried in carbon to change airflow. Small problems can create measurable losses.
GDI Injector Cleaning
Gasoline direct injectors are exposed to high temperature, combustion pressure and deposit-forming conditions. When the injector tip gets dirty, spray pattern and fuel atomization suffer.
Intake Valve Deposit Control
In GDI engines, gasoline does not wash over the intake valves the way it does in port-injected engines. Cleaner airflow helps the engine operate closer to the way it was designed.
Combustion Chamber Cleaning
Combustion chamber deposits can increase hot spots and contribute to knock. The engine may reduce ignition timing to protect itself, which can reduce power.
Throttle Response
Drivers often notice deposit problems as a dull or lazy feeling when they press the accelerator. Cleaning the system can improve response.
Fuel Economy Support
Dirty injectors can reduce combustion efficiency. Cleaning the system helps support cleaner, more complete combustion.
Emissions Support
Deposits can contribute to incomplete combustion, higher hydrocarbons and particulate output. A cleaner fuel system helps the engine burn fuel more cleanly.
Testing & Results
Proof Matters: AMSOIL P.I. Has Published Performance Claims
Fuel additive marketing can get ridiculous fast. Every bottle on the shelf claims to clean something, restore something or improve something. That is why testing matters.
Horsepower Restoration
AMSOIL reports up to 14% horsepower restoration after one treatment in third-party chassis dyno testing on a high-mileage 2016 Chevrolet Silverado 5.3L.
GDI Injector Flow Restoration
AMSOIL also reports restoration of GDI injector flow after treatment. Injector flow affects spray pattern, combustion quality, power, idle quality and fuel economy.
The right expectation is not magic in a bottle. If deposits are causing the performance loss, cleaning those deposits can restore performance the engine already had.
Application
How to Use AMSOIL P.I.
AMSOIL P.I. goes directly into the fuel tank and works as the engine runs on the treated gasoline.
Add at Fill-Up
Pour the bottle into the fuel tank before or during fueling.
Drive Normally
P.I. works while the engine runs. Longer drives and sustained operating temperature are best.
Repeat Every 4,000 Miles
AMSOIL recommends using P.I. every 4,000 miles for continued deposit control.
Treatment Rate
One bottle treats up to 20 U.S. gallons of gasoline. For larger tanks, follow AMSOIL directions on the product label.
Compatible With
- Gasoline passenger cars
- Gasoline light trucks
- GDI gasoline direct injection engines
- Port fuel injected engines
- Turbocharged gasoline engines
- Catalytic converters
- Oxygen sensors
Not for Use In
- Diesel engines
- Two-stroke engines
- Premix fuel applications
Common Questions
AMSOIL P.I. Frequently Asked Questions
You can buy AMSOIL P.I. directly from AMSOIL through an authorized dealer link. The buy buttons on this page take you to AMSOIL with the Vyscocity dealer code applied.
Yes, when the issue is deposit-related. It will not repair worn mechanical parts, bad ignition components or failed sensors.
AMSOIL recommends using P.I. every 4,000 miles for ongoing deposit control.
Yes. GDI engines are one of the best use cases because they are prone to deposit problems around injectors and intake valves.
No. AMSOIL P.I. is for gasoline engines only.
Sea Foam is a broad-use fuel system cleaner. AMSOIL P.I. is a concentrated gasoline detergent treatment aimed at modern gasoline engines, including GDI engines.
Related Products
Related AMSOIL Fuel System Products
Buy Through an Authorized Dealer
Get AMSOIL P.I. Performance Improver
If your gasoline engine feels sluggish, idles rough or has never had a serious fuel system treatment, AMSOIL P.I. is an easy first step. One bottle treats up to 20 gallons and works through normal driving.
Vyscocity is an authorized AMSOIL dealer serving the USA and Canada. Red Seal 310T Truck & Coach Technician. AMSOIL dealer since 2006.