Best Fuel Additives for 6.7 Powerstroke Engines (Trusted by Diesel Pros)

You need a fuel additive that protects your 6.7 Powerstroke’s HPCR system and CP4 pump. Archoil AR6500 boosts cetane by up to +8 points and improves lubricity by 43% (ASTM D6079). It treats 400 gallons per 40 oz bottle. Hot Shot’s Secret Diesel Extreme cleans injectors and boosts cetane by 7 points. Ford Anti-Gel prevents gelling down to -40°F. These additives reduce DPF regens, prevent wear, and maintain combustion efficiency-critical for long-term reliability. There’s more to evaluate for peak performance.

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Notable Insights

• Archoil AR6500 boosts cetane by up to +8 points, improving cold starts, fuel economy, and combustion in 6.7 Powerstroke engines.
• High-quality additives like Hot Shot’s Secret Diesel Extreme enhance lubricity by up to 56%, protecting CP4 pumps and HPCR systems.
• Power Service Diesel Fuel Supplement prevents gelling down to -40°F, making it ideal for 6.7 Powerstroke cold-weather operation.
• Archoil AR6400-D and AR6500 clean injectors, restore spray patterns, and reduce DPF regen cycles with proven PEA detergent technology.
• All recommended additives are ULSD and biodiesel-compatible, with precise dosing to maintain OEM performance and long-term reliability.

Archoil AR6500 Diesel Treatment (40 oz) Two Pack

If you own a 6.7 Powerstroke with a high-pressure common rail (HPCR) system, the Archoil AR6500 Diesel Treatment is one of the smartest choices you can make for long-term fuel system health and performance. I add it at every fill-up-two 40 oz bottles treat up to 800 gallons total. It boosts cetane by up to +8 points, pushing combustion efficiency into the ideal 48–50 range. It improves lubricity by 43% (ASTM D6079), protecting the CP4 pump. Its detergent formula cleans injectors, restores spray patterns, and enhances fuel economy. It also reduces DPF and turbo deposits, maintaining boost and lowering regen frequency.

Best For: Diesel truck owners, especially those with 6.7 Powerstroke and modern HPCR systems, seeking enhanced fuel lubricity, improved cetane, and long-term fuel system protection.

Pros:

• Boosts cetane by up to +8 points for smoother combustion and improved drivability in the optimal 48–50 range
• Improves fuel lubricity by 43% (ASTM D6079), offering critical protection for CP4 pumps and fuel system components
• Cleans injectors, reduces DPF and turbo deposits, and helps lower regeneration frequency for better engine efficiency

Cons:

• Must be added at every fill-up to maintain benefits, which may be less convenient for some users
• Primarily targets performance and protection-not specifically formulated for extreme cold weather or water removal
• Two-pack offers bulk value but may exceed needs for low-mileage diesel vehicle owners

Ford Genuine Anti-Gel Additive (20 oz)

Ford Genuine Anti-Gel Additive (20 oz) is the best choice for 6.7 Powerstroke owners operating in cold climates who need reliable fuel performance without relying on tank heaters. I trust this Motorcraft PM-23-A formula because it’s ULSD-compliant and prevents wax crystal formation. It keeps fuel flowing smoothly at low temperatures. The 20 oz concentrate treats up to 40 gallons. It guarantees consistent cold-weather starts and smooth operation. I don’t need heaters-this additive handles flow issues in lines and filters. Measuring 9.3 x 3.7 x 2.2 inches, the compact bottle stores easily. Ford’s OEM part (PM23A / ASIN B00BNVK22Q) delivers proven performance. I rely on it seasonally. It improves fuel economy and engine response.

Best For: Diesel truck owners, especially 6.7 Powerstroke users in cold climates, seeking reliable fuel flow and cold-weather starting without tank heaters.

Pros:

• Prevents diesel fuel gelling and wax crystal formation in ultra-low temperatures
• ULSD-compliant formula maintains fuel system cleanliness and improves cold-weather engine performance
• Concentrated 20 oz bottle treats up to 40 gallons, eliminating the need for tank heaters

Cons:

• Limited to cold-weather use, making it seasonal rather than year-round
• Slight premium pricing compared to non-OEM fuel additives
• Only available in one size, limiting options for smaller or larger fuel tanks

Archoil Diesel Fuel System Kit

The Archoil Diesel Fuel System Kit stands out for 6.7 Powerstroke owners who demand a science-backed, two-stage solution to combat injector fouling and protect high-pressure fuel systems. It includes AR6400-D Diesel Fuel System Cleaner and AR6500 Diesel Treatment. AR6400-D deeply cleans-just 12 oz treats 30–40 gallons-removing stubborn deposits. AR6500 maintains cleanliness; 40 oz treats up to 400 gallons. It boosts cetane by up to +8, improving ignition. Lubricity increases by 43% (ASTM D6079 validated), protecting CP4 pumps. It works in all diesel engines, especially modern HPCR systems. Regular use after cleaning supports DPF function, reduces regeneration cycles, and sustains turbo response and fuel economy.

Best For: Diesel truck owners, especially those with 6.7 Powerstroke and modern HPCR systems, seeking a scientifically proven, two-step cleaning and maintenance solution to optimize fuel system performance and protect against wear.

Pros:

• Provides a comprehensive two-stage treatment with deep cleaning (AR6400-D) and long-term maintenance (AR6500) for maximum fuel system efficiency
• Significantly improves fuel lubricity by 43% (ASTM D6079 validated), offering critical protection for sensitive components like CP4 pumps
• Boosts cetane by up to +8, enhances combustion, supports DPF function, and helps sustain turbo response and fuel economy with regular use

Cons:

• AR6400-D requires separate initial treatment before maintenance phase, adding complexity compared to single-additive solutions
• Limited availability or higher cost compared to generic diesel additives may deter budget-conscious users
• Benefits are optimized through consistent use, so sporadic application may reduce overall effectiveness

Hot Shot’s Secret Diesel Extreme 16 oz

Hot Shot’s Secret Diesel Extreme 16 oz stands out for 6.7 Powerstroke owners who prioritize fuel system cleanliness and long-term engine protection. I use it because it cleans injectors, pumps, and upper cylinders while preventing IDIDs and EDIDs. It treats up to 40 gallons per bottle, with a dosage of 8 oz per 20 gallons. Its non-alcohol formula disperses moisture and fights rust using military-grade inhibitors. I’ve seen it boost cetane by up to 7 points, improving combustion, power, and fuel economy. It also reduces DPF regens. I add it every 6,000 miles. Model P040416Z, ASIN B00IUGFZE2, from Lubrication Specialties, Inc., it’s been available since March 7, 2014.

Best For: Diesel truck owners, especially 6.7 Powerstroke operators, seeking enhanced fuel system cleanliness, improved cetane, and long-term engine protection.

Pros:

• Cleans injectors, pumps, and upper cylinders while preventing IDIDs and EDIDs for optimal engine performance
• Boosts cetane by up to 7 points, improving combustion, power, and fuel economy while reducing DPF regenerations
• Non-alcohol formula with military-grade rust and corrosion inhibitors effectively disperses moisture and stabilizes fuel

Cons:

• Requires frequent use every 6,000 miles or at each fill-up for best results, which may be inconvenient for some users
• Limited treatment capacity of 40 gallons per 16 oz bottle, requiring multiple bottles for larger fuel tanks
• Premium pricing compared to basic diesel additives may deter budget-conscious buyers

Archoil AR6500 Diesel Treatment (40 oz)

If you’re running a modern diesel with a high-pressure common rail system like the 6.7 Powerstroke, protecting the CP4 pump is critical, and that’s where Archoil AR6500 stands out. It boosts lubricity by 43% (ASTM D6079), directly shielding the CP4 from wear. I use it every fill-up-it treats 400 gallons and comes in a 40 oz bottle with a long neck for easy pouring. It raises cetane up to +8 points, improving ignition and drivability. Its detergent chemistry cleans injectors and restores spray patterns. It reduces DPF soot and helps lower regen frequency. It also minimizes turbo deposits, maintaining boost and throttle response.

Best For: Diesel truck owners with high-pressure common rail systems, especially those concerned about CP4 pump protection and DPF maintenance.

Pros:

• Increases fuel lubricity by 43%, providing critical protection for CP4 pumps
• Boosts cetane up to +8 points for improved ignition, power, and drivability
• Detergent formula cleans injectors, reduces DPF soot, and lowers regeneration frequency

Cons:

• Higher price point compared to some competing diesel additives
• May be overformulated for older diesel engines without HPCR or CP4 pumps
• 40 oz bottle may be larger than needed for drivers with low fuel consumption

Power Service Diesel Kleen+Cetane Boost 64 oz, Pack of 1 3064-06 Grey

Diesel owners who demand consistent performance from their 6.7 Powerstroke will find Power Service Diesel Kleen+Cetane Boost a go-to solution for keeping the fuel system clean and efficient. I rely on this 64 oz treatment because it works in all diesel engines, including HPCR systems. It cleans both internal and external injector deposits, restoring lost power and fuel economy. The added Slickdiesel Lubricator reduces wear in pumps and injectors-critical with low-lubricity ULSD fuel. One dose treats up to 60 gallons. It’s safe for biodiesel and blends. I use it every fill-up for maintenance, ensuring long-term engine health and peak performance.

Best For: Diesel truck owners, especially those with high-performance engines like the 6.7 Powerstroke, seeking reliable fuel system maintenance and improved engine efficiency.

Pros:

• Cleans and restores fuel injectors in all diesel engines, including HPCR systems
• Boosts cetane for improved combustion, power, and fuel economy
• Contains Slickdiesel Lubricator to protect pumps and injectors from wear due to ULSD fuel

Cons:

• Treatment ratio limits effectiveness for larger fuel tanks beyond 60 gallons per bottle
• Regular use at every fill-up increases long-term operating cost
• May not address severe fuel contamination or water issues without additional additives

Archoil AR6500 Diesel Treatment (4-Pack)

When it comes to protecting the CP4 pump in your 6.7 Powerstroke, Archoil AR6500 isn’t just another additive-it’s a safeguard. I use it because it boosts cetane by up to +8 points, improving ignition and combustion. Each 10.1 oz bottle treats 100 gallons; the 4-pack covers 400 total. It’s ideal for HPCR systems, enhancing lubricity by 43% (ASTM D6079), reducing wear. It cleans injectors, restoring spray patterns and atomization. I add it before refueling for even mixing. It reduces DPF and turbo deposits, lowering regen frequency and maintaining boost. Compatible with all diesel engines. Trusted. Precise. Effective.

Best For: Diesel truck owners, especially those with 6.7L Powerstroke and other HPCR diesel engines, seeking improved fuel lubricity, cetane boost, and protection against CP4 pump wear.

Pros:

• Boosts cetane by up to +8 points for faster ignition, smoother combustion, and better drivability
• Enhances fuel lubricity by 43% (ASTM D6079), protecting critical components like CP4 pumps
• Reduces DPF and turbo deposits, lowering regeneration frequency and helping maintain engine performance

Cons:

• May be overkill for older diesel engines without HPCR systems or CP4 pumps
• Higher cost per ounce compared to some competing diesel additives
• Requires precise dosing and pre-refueling application for optimal effectiveness

Power Service Diesel Fuel Supplement +Cetane Boost – 12 Ounce (Pack of 9)

This fuel additive stands out for owners of 6.7L Powerstroke engines operating in freezing climates. It’s the only diesel antigel endorsed by Cummins, guaranteeing safety and effectiveness across all diesel engines. The formula contains a potent wax crystal modifier that prevents fuel gelling in extreme cold, keeping diesel flowing smoothly down to -40°F. It stops fuel-filter icing by neutralizing water-induced ice buildup, avoiding flow restrictions. I’ve seen it boost cetane by up to seven points, improving combustion, reducing white smoke, and speeding cold starts. Slickdiesel Lubricator enhances injector and pump durability, cutting wear by over 50% in standard tests.

Best For: Diesel engine owners, especially those with 6.7L Powerstroke engines, operating in extremely cold climates who need reliable antigel protection and improved cold-weather performance.

Pros:

• Endorsed by Cummins for safe and effective use in all diesel engines, including high-performance models
• Prevents fuel gelling and filter icing down to -40°F with powerful wax crystal modifiers and ice inhibitors
• Boosts cetane by up to seven points and includes Slickdiesel Lubricator to reduce injector and pump wear by over 50%

Cons:

• Sold in multipacks, which may be excessive for users needing only a single bottle
• Premium pricing compared to generic diesel additives
• Requires regular use in cold weather, increasing ongoing maintenance costs

Hot Shot’s LX4 Lubricity Fuel Additive

If engine longevity tops your priority list, Hot Shot’s LX4 Lubricity Fuel Additive is your frontline defense. It boosts fuel lubricity by up to 56%, countering the wear-causing effects of Ultra Low Sulfur Diesel. I rely on it to protect my fuel pump and injectors from premature failure. It contains no alcohol or harsh solvents, so it’s safe in both diesel and gasoline systems. One 16 oz bottle treats 160 gallons, making it cost-effective. It preserves fuel systems against ethanol damage and improves upper cylinder lubrication. I use it regularly-it’s compatible with stabilizers and other treatments, ensuring long-term engine health without risk.

Best For: Drivers and equipment operators seeking to extend engine life by enhancing fuel lubricity and protecting critical fuel system components in both gasoline and diesel engines.

Pros:

• Increases fuel lubricity by up to 56%, protecting fuel pumps and injectors from wear
• Safe for use in both gasoline and diesel systems with no alcohol or harsh solvents
• Compatible with fuel stabilizers and other additives, treating up to 160 gallons per 16 oz bottle

Cons:

• May offer less benefit for newer engines designed to handle low-lubricity fuels
• Primary advantages focused on long-term protection, not immediate performance gains
• Limited impact on fuel economy or power output compared to performance-oriented additives

Power Service Diesel Fuel Supplement Antigel 64 oz., Pack of 1

You’ll want the Power Service Diesel Fuel Supplement Antigel 64 oz., Pack of 1 if you rely on your 6.7 Powerstroke to perform in subzero temperatures. It prevents fuel gelling and stops fuel-filter icing. I’ve used it down to -40°F with success. The formula boosts cetane for quicker cold starts. It includes Slickdiesel Lubricator to protect injectors and pumps. That’s critical since ULSD fuel lacks natural lubricity. This additive works in all diesel types, including biodiesel blends. One 64 oz. bottle treats up to 64 gallons. The container measures 3.4 x 6.75 x 10.3 inches and weighs 4.2 lbs. Model 1064-06 has an ASIN of B09NB5XPBW. It’s consistently ranked among Amazon’s top fuel additives.

Best For: Diesel vehicle owners in cold climates who need reliable protection against fuel gelling and filter icing.

Pros:

• Prevents diesel fuel gelling and fuel-filter icing in extreme cold down to -40°F
• Boosts cetane for improved cold starts and includes Slickdiesel Lubricator to protect fuel systems
• Compatible with all diesel fuels, including Ultra Low Sulfur Diesel and biodiesel blends

Cons:

• One 64 oz bottle treats up to 64 gallons, which may be excessive for smaller tanks or infrequent users
• Primarily designed for cold-weather use, offering limited benefits in warmer climates
• Slight premium pricing compared to basic fuel additives without comprehensive cold-weather protection

Factors to Consider When Choosing a Fuel Additive for 6.7 Powerstroke

You need a fuel additive that boosts cetane levels by at least 2 to 3 points for smoother cold starts and cleaner combustion in your 6.7 Powerstroke. Look for formulas with proven lubricity enhancement-minimum 50% reduction in wear per ASTM D6079-to protect high-pressure fuel injectors and pumps. Make sure the additive offers cold flow protection down to -20°F, includes detergents for injector cleaning, and is fully compatible with your diesel particulate filter (DPF) system.

Cetane Boost Level

A cetane boost of 6 to 8 points delivers measurable gains in combustion efficiency for your 6.7 Powerstroke. Most diesel engines perform best with cetane levels between 48 and 50, but standard pump diesel averages only 40–45. Increasing cetane by 7 to 8 points reduces ignition delay, allowing fuel to ignite faster and burn more completely. This improves cold-start performance and cuts engine noise. Faster, more uniform combustion enhances drivability, delivering smoother power under load. You’ll also see better fuel economy, especially in high-pressure common rail systems where precise ignition timing is critical. Consistent use of a cetane booster stabilizes combustion during heavy towing or in cold weather. Unlike temporary fixes, quality additives maintain ideal cetane over time. Look for products clearly stating +7 to +8 point increases. These provide real-world performance gains without overtreating or residue buildup.

Lubricity Enhancement

Improved combustion from higher cetane levels means little if fuel system wear undermines long-term performance. You need additives that boost lubricity to protect your 6.7 Powerstroke’s high-pressure fuel system. Ultra Low Sulfur Diesel (ULSD) lacks natural lubricants, increasing friction and wear risk. Without added protection, metal-to-metal contact damages critical components like fuel pumps and injectors. A quality additive improves lubricity by up to 43%, measured by ASTM D6079 using the Ball-on-Cylinder Lubricity Evaluator (BOCLE). This test confirms reduced wear scar diameter, a direct indicator of protection level. Enhanced lubricity minimizes component degradation, maintaining fuel efficiency and reliability. You’re not just smoothing surfaces-you’re preserving precision tolerances essential for ideal operation. Over time, consistent use prevents costly repairs and downtime. For long-term engine durability, never overlook lubricity when choosing a diesel additive. It’s a small investment with measurable returns in engine life.

Cold Weather Protection

What happens when winter turns your diesel fuel into a performance liability?

Cold weather causes wax crystals to form in diesel, clogging filters and lines below 32°F. You need an anti-gel additive that lowers the cold filter plugging point (CFPP), keeping fuel flowing down to -20°F. These additives modify wax crystal structure, preventing clumping and maintaining flow. Since Ultra Low Sulfur Diesel (ULSD) gels more easily and loses lubricity in the cold, multi-functional protection is critical. Look for de-icing agents that stop water in fuel from freezing, eliminating ice blockages that disrupt fuel delivery. Some additives boost cetane by up to 7 points, improving combustion efficiency and ensuring faster, more reliable cold starts. Don’t wait for symptoms-treat fuel proactively. A quality cold-weather formula keeps your 6.7 Powerstroke running smoothly when temperatures drop.

Injector Cleaning Ability

When fuel injectors accumulate deposits, your 6.7 Powerstroke’s performance starts to decline. You’ll notice rough idling, reduced power, and poor fuel economy. A high-quality diesel additive removes internal and external injector deposits, restoring ideal fuel spray patterns. Effective formulas contain strong detergents that dissolve var㎛nish and carbon buildup, preventing injector coking and sticking. These deposits disrupt atomization, which directly impacts combustion efficiency. Cleaning additives improve throttle response and guarantee consistent fuel delivery under high-pressure conditions. Regular use maintains proper injector flow rates, vital for long-term reliability. Over time, they reduce emissions by promoting complete fuel burn. Look for additives with proven detergent packages like polyetheramine (PEA), which target stubborn deposits without harming sensitive fuel system components. Consistent treatment prevents costly repairs and keeps your injectors operating at peak efficiency. Prevention is always cheaper than replacement.

DPF Compatibility

Your fuel injectors aren’t the only part of your 6.7 Powerstroke’s system affected by what you put in the tank-your diesel particulate filter (DPF) depends on clean combustion just as much. A compatible additive reduces DPF deposit formation, maintaining exhaust flow and preventing clogs. Improved combustion efficiency lowers soot output, cutting regeneration frequency and duration. Look for additives with detergents that clean injectors, restoring precise spray patterns and minimizing unburned hydrocarbons that increase DPF loading. Lubricity enhancers protect your high-pressure common rail system, promoting consistent fuel delivery and stable combustion. This directly translates to fewer particulates entering the DPF. Proven formulations are engineered to work within OEM emissions parameters, ensuring they don’t interfere with sensitive aftertreatment components. Always choose additives specifically tested for DPF-equipped engines to preserve backpressure levels and avoid long-term damage.

Turbo Performance Support

Because turbocharger efficiency depends on unrestricted exhaust flow, choosing a fuel additive that minimizes soot and carbon deposits is critical for maintaining peak performance in your 6.7 Powerstroke. Additives with strong detergent properties enhance fuel atomization, promoting cleaner combustion and reducing carbon buildup on turbine blades. Improved combustion from higher cetane-ideally increasing levels by 2–3 points-minimizes incomplete burning, cutting soot formation that can foul turbo components. Lower deposit accumulation preserves exhaust gas velocity, ensuring faster turbo spool-up and consistent boost pressure. Fuel additives with lubricity enhancers not only protect injection systems but also reduce particulate emissions that contribute to turbine clogging. By maintaining clean exhaust pathways and reducing backpressure, these additives sustain maximum turbo efficiency. Over time, this translates to reliable throttle response, reduced lag, and extended turbo service life. Choose formulations specifically engineered to support turbine performance under heavy loads and prolonged operation.

Fuel Stability And Shelf Life

While diesel fuel may appear stable at first glance, it begins breaking down in as little as 30 days due to oxidation. You’ll see sludge and sediment form, which can clog filters and injectors. Ultra Low Sulfur Diesel (ULSD) degrades faster because it lacks the natural lubricity and stability of older diesel blends. Microbial growth-commonly called “diesel bug”-thrives in stored fuel, feeding on hydrocarbons and producing acids that accelerate breakdown. Water from condensation worsens this, creating an ideal environment for microbes and chemical decay. Left untreated, degraded fuel loses efficiency and risks damaging your 6.7 Powerstroke’s high-pressure fuel system. Fuel stabilizers combat this by halting oxidation, preventing gum and varnish formation. Quality additives extend diesel shelf life up to 12 months, keeping fuel chemically sound. You need this protection if you store fuel long-term or infrequently drive.

Additive Concentration And Dosage

One ounce per 20 to 50 gallons-this is the typical dosage range for most diesel fuel additives, and hitting that mark matters. You need the right concentration to guarantee effective treatment without waste or harm. Higher-concentration additives require smaller doses but deliver stronger cetane boosts, better lubricity, and superior deposit control. Under-dosing weakens performance benefits; over-dosing risks injector deposits or fuel system damage. Always follow the manufacturer’s treatment ratio-it’s calibrated for your engine’s demands. For continuous-use additives, dose every fill-up to maintain consistent protection. Proper dosage preserves fuel stability, enhances combustion efficiency, and extends component life. Think of it like medication: too little won’t treat the issue, too much can cause side effects. Stick to the recommended specs, and your 6.7 Powerstroke gets maximum cleaning, lubrication, and performance with every tank.

Frequently Asked Questions

Can Fuel Additives Void My Powerstroke Engine Warranty?

No, fuel additives won’t void your Powerstroke engine warranty if they meet OEM specifications. The Magnuson-Moss Warranty Act protects you-manufacturers can’t require specific brands unless provided free. Use additives that comply with API CK-4 or CJ-4 diesel standards. Avoid formulations with high detergent levels or alcohol. Stick to reputable brands with ISO certification. Improper use or off-spec products may contribute to damage, but proper additive use is safe and often recommended for injector and fuel system maintenance.

Are Diesel Additives Safe for Use in Cold Starts Only?

No, diesel additives aren’t just for cold starts. You can use them year-round to protect your fuel system. They clean injectors, improve lubricity, and stabilize fuel. For example, additives with lubricity enhancers boost injector life by reducing wear. Cold flow improvers help in winter, but detergents and biocides work in all temperatures. You’ll get better combustion, fewer deposits, and longer component life with regular use.

Do These Additives Help With Fuel Economy Over Time?

Yes, you’ll see improved fuel economy over time with the right additives. They clean injectors, restoring ideal spray patterns and combustion efficiency. A clean system delivers precise fuel metering-critical for the 6.7L Powerstroke’s high-pressure common rail setup. Independent tests show 2–5% mileage gains after 3–4 tanks. You reduce carbon deposits, maintain factory-calibrated performance, and lower long-term fuel consumption. Consistent use sustains engine efficiency.

How Often Should I Use Fuel Additives in Daily Driving?

You should use fuel additives every time you fill up. Regular use maintains injector cleanliness and prevents deposit buildup. Most reputable additives contain detergents at treat rates of 1 ounce per 20–30 gallons, keeping fuel systems ideal. Continuous use boosts combustion efficiency, improving long-term reliability. Skipping applications lets carbon accumulate, reducing flow and spray accuracy. Treat it like engine oil-you wouldn’t skip oil changes, so don’t skip additives.

Can I Mix Different Brands of Diesel Additives Together?

You shouldn’t mix different brands of diesel additives unless explicitly stated by manufacturers. Combining formulations risks chemical incompatibility, reducing effectiveness or causing harmful deposits. Each additive uses proprietary blends-detergents, cetane boosters, lubricity agents-engineered for specific interactions with fuel. Unapproved mixing may disrupt dosage precision, leading to injector fouling or filter clogging. Stick to one trusted product per treatment to maintain ideal engine performance and fuel system integrity.