STP

STP Octane Booster Fuel Additive — 5.25 fl oz Bottle, Pack of 12 — Raises Octane & Cleans Fuel Intake

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$72.50

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Why customers choose NorthTrail Auto

STP Octane Booster is a 2‑in‑1 fuel additive that raises octane while cleaning the fuel intake system to help restore power and smoother acceleration.

If your engine feels sluggish or you hear occasional knocking, STP Octane Booster combines MMT and a synthetic cleaning technology in a jet‑fuel carrier to address both octane needs and deposits in the fuel intake. Each 5.25 fl oz bottle is designed to treat up to 15 gallons of gasoline and is compatible with all gasoline engines, including cap‑less fuel systems. Use one bottle with every fill‑up to help maintain optimal combustion and fuel flow.

How does STP Octane Booster reduce engine knock and pinging?

STP's formula includes MMT, an octane‑raising additive that increases the fuel's resistance to premature combustion. By elevating octane, the additive helps lower the chance of knock and pinging caused by deposits or lower‑grade gasoline. It does not change engine tuning but improves the fuel's ability to burn more smoothly under compression.

  • MMT raises octane rating to resist pre‑ignition.
  • Reduces audible knock and rough combustion events.
  • Helps maintain consistent ignition timing across operating conditions.

What cleaning effect does this fuel treatment have on the intake system?

The synthetic technology in STP Octane Booster targets deposits that build up in the fuel intake and combustion areas, helping to restore fuel flow and combustion efficiency. Regular use helps loosen and remove varnish and carbon residues that can restrict injectors and intake valves. Cleaner fuel pathways support smoother acceleration and can help engines deliver designed horsepower more reliably.

  • Breaks down varnish and carbon build‑up in the intake and injectors.
  • Promotes steadier fuel flow and more even spray patterns.
  • Supports more complete combustion for smoother throttle response.

How do I use STP Octane Booster and how much fuel does one bottle treat?

Using the product is straightforward: pour the entire 5.25 fl oz bottle into your gas tank before or after filling. One bottle treats up to 15 gallons of gasoline, so match usage to your tank size or use with every fill‑up for ongoing maintenance. It works with standard gas caps and cap‑less systems.

  • Pour full bottle into tank before or after fueling.
  • Treats up to 15 gallons per 5.25 fl oz bottle.
  • Safe for cap‑less systems and most gasoline engines when used as directed.

Will STP Octane Booster affect my fuel economy?

STP Octane Booster is formulated with a high‑quality jet‑fuel carrier and additives intended to improve combustion efficiency. By optimizing how fuel burns and reducing engine strain from knocking, the treatment can help the engine use fuel more effectively. While individual MPG gains depend on vehicle condition and driving habits, regular use supports more efficient fuel consumption.

  • Jet‑fuel carrier helps deliver active ingredients reliably through the system.
  • Cleaner combustion can translate to steadier fuel economy over time.
  • Results vary by vehicle age, driving style, and baseline maintenance.

Who is this product for: STP Octane Booster is aimed at drivers wanting an easy, affordable way to address knocking, restore responsiveness, and keep the fuel intake system cleaner between service intervals. It's suitable for daily commuters, older vehicles showing deposit‑related symptoms, and anyone who prefers to maintain performance using a simple pour‑in treatment compatible with cap‑less and conventional gasoline systems.

FAQ

Q: Is STP Octane Booster safe for cap‑less fuel systems?

A: Yes. The formula is compatible with cap‑less systems and all gasoline engines when used as directed.

Q: How often should I use one 5.25 fl oz bottle?

A: Use one bottle with each fill‑up or as needed; each treats up to 15 gallons of gasoline.