Red Line Complete SI-1 Fuel System Cleaner, a detergent and lubricant that will give great results in vehicles with both fuel injectors (including the latest direct gasoline-injection models) and carburetors.
Considerations when choosing fuel injector cleaners
Fuel injector cleaners usually contain two components: a detergent to cut through greasy deposits and a lubricant that helps reduce wear and provides a protective layer that inhibits further buildup. Many are designed to work not just with the fuel injectors, but throughout the system, including the combustion chambers. Deposits are completely dissolved within the product, so they can't cause obstructions in the exhaust system or damage catalytic converters.
When comparing different products, you need to ensure they are suitable for your engine. Some work with gasoline and diesel, but others are fuel specific. Some work with fuel injectors and carburetors, others are targeted at injectors only. If your vehicle is fitted with the latest direct gasoline injection (DGI) system, it's important to ensure compatibility. Wherever possible, check suitability with vehicle make, model, and year.
There can be some confusion between detergents and solvents. They are not the same thing. Older formulations may use solvents as part of the detergent composition, but these are not environmentally friendly. Modern versions are often solvent-free (though don't assume that means nontoxic).
Do they actually work?
Auto mechanics advise regular use of fuel injector cleaners to ensure the long-term health and performance of your engine -- yet any review of these products invariably shows up a few comments from users who say that a particular product just didn't work.
The most important point here is that a fuel injector cleaner's main purpose is to stop deterioration. They can't make a vehicle better than when it left the showroom. Also, differences will almost always be more pronounced on older vehicles than on newer models. While fuel injector cleaners can help fix problems such as poor starting, lumpy idling or smoking, the number-one benefit is to maintain engine performance, and prevent damage to vital components that are expensive to repair.
We would caution against buying 'no-name' fuel injector cleaners. Top brands have a reputation to protect and are likely to have made the necessary investment to ensure their product is effective.
There's little point in comparing packs and prices directly. Sizes vary considerably, and two packs of the same size often treat different amounts of fuel -- so it's important to check how much you need to use and how often. The cheapest fuel injector cleaners are designed to be added to each tank of gas, others less often. We did the math on a wide range of products to give an average per mile, and the majority work out at a half cent or less, so cost is no barrier to proper protection.
Q. Should I ask a mechanic to service my fuel injectors?
A. You can, but it will probably cost upwards of fifty dollars. The cleaners do no harm so it's an economical first step. If you still have problems with rough running after treatment, that's probably when you need your local auto mechanic.
Q. Can I use fuel injector cleaner for my motorcycle?
A. The top products we looked at will work with any gas engines, so that includes motorcycles, ATVs, snowmobiles, etc. We have heard that a few may not, so it is worth checking each product before you order.
Fuel injector cleaners we recommend
Best of the best: Red Line's Complete SI-1 Fuel System Cleaner
What we like: Renowned for performance improvements in all gasoline engines: trucks, cars, motorcycles, marine engines, etc., and injectors or carburetors. Reduces valve and combustion-chamber deposits. Also contains upper cylinder lubricant.
What we dislike: More expensive than some. Not for diesel motors (use Red Line 70802 85 Plus).
Best bang for your buck: Lucas' Upper Cylinder Lubricant and Injector Cleaner
Our take: Affordable and efficient product for all internal combustion engines.
What we like: Low cost and very popular blend of lubricants and detergents works with fuel injectors and carburetors. Neutralizes low-sulphur diesel and reduces harmful gasoline emissions.
What we dislike: Nothing, though there are those who report seeing no real change after use.
Choice 3: Royal Purple's 18000 Max Fuel Injector Cleaner
Our take: Inexpensive product for diesel and gas motors, from one of the top brands.
What we like: Good all-round solution claims to maximize efficiency and therefore improve both power and fuel economy. Stabilizes ethanol, which can damage injectors and pumps.
What we dislike: Poor bottle design -- can be difficult to pour into tank openings.
Bob Beacham is a writer for BestReviews. BestReviews is a product review company with a singular mission: to help simplify your purchasing decisions and save you time and money. BestReviews never accepts free products from manufacturers and purchases every product it reviews with its own funds.
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