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Amsoil PI Performance Improver Premium Fuel Additive

Last updated: February 22nd, 2026
Amsoil P.I. Performance Improver Premium Fuel Additive (API)

Amsoil Performance Improver is the ideal additive to help restore and maintain the power and reliability your engine was designed to have. Over time your engine becomes contaminated and hindered by deposits, sludge and other contaminants that reduce engine performance. Your fuel needs help to get rid of these deposits and Amsoil Performance Improver is the absolute best way to do it. In addition to a better performing engine, you will have lower emissions, improvements in gas mileage up to five percent and better engine response.

Available Packaging for API

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Technical Info PDF

This product will typically ship within 24 hours from one of Amsoils 14 distribution centers in North America. This means that the product will ship to you from the closest possible location and most orders end up arriving in two to three days or less! Expedited shipping options are available as well.

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Amsoil PI Frequently Asked Questions
Amsoil PI cleans fuel injectors, intake valves, and combustion chambers to restore power, improve fuel economy, and reduce emissions using just one tank of treated fuel.
Testing showed an average fuel economy increase of 2.3 percent, with some vehicles gaining up to 5.7 percent after one tank treated with Amsoil PI.
Yes. Amsoil PI reduces hydrocarbons, carbon monoxide, and nitrogen oxides. It is recommended before emissions testing to improve results.
Use one bottle every 4,000 miles or every 100 hours of engine operation. For large tanks, use two bottles in up to 40 gallons of fuel.
Yes. It is safe for catalytic converters, oxygen sensors, and ethanol-blended fuels. It is not recommended for two-cycle engines.
Deposits form during hot soak periods when gasoline degrades inside the injector. Poor fuel quality and short trips make this worse.
Intake valve deposits restrict airflow, disrupt fuel ratios, and can cause valve sticking or burning. This leads to power loss and higher emissions.
Carbon rap happens when piston deposits interfere with the cylinder head. Amsoil PI removes these deposits to reduce knock and restore power.
Yes. By cleaning combustion chamber deposits, Amsoil PI helps control knock and reduces the need for higher-octane fuel in older engines.
Amsoil PI is combustible and harmful if swallowed or inhaled. Avoid skin and eye contact and read all safety instructions on the container.

The Performance Oil Company

An Authorized Amsoil Dealer
Allenton, Wisconsin 53002
(262)-388-3411