Fuel Injector Cleaner: Believe the Performance Improvement Promises or Steer Clear of It?
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Fuel Injector Cleaner: Believe the Performance Improvement Promises or Steer Clear of It?

Fuel injector cleaning products and services are mostly just clever advertising since gasoline is required to have detergents anyway

September 21, 2021

We've all seen the advertisements on TV, in magazines, and in the automotive section of our local stores for fuel injector cleaner. The advertisements typically promise performance gains and better fuel economy, not to mention a very convincing before and after comparison photo showing how much cleaner your fuel injectors can become. But how much truth is there to all the hype and advertisements?

those little bottles have their limits

Honestly, there's not much to be gained from adding fuel injector cleaner to your gas tank. While it is possible to clean some deposits from the fuel system simply by pouring the contents of a container into the gas tank, it's really not as effective as the marketing will have you believe.

To properly clean a part of the fuel system with heavy deposits, the system needs to be drained and portions of it disassembled. Only then can the fuel system components, such as few injectors, be properly and thoroughly cleaned.  To effectively clean a dirty fuel injector, high concentrations of cleaner need to be pushed through it using specialized equipment. You simply can't get these concentrations by adding a 3 ounce container of cleaner to a gas tank.

you need a professional clean to make an immediate difference

There are services available at shops where concentrated cleaner is pushed through your entire fuel injection system. Some of these can be beneficial, but only if you are truly experiencing problems caused by deposits. If you are running into trouble codes that point to misfires that are diagnosed as clogged fuel injectors, then this service might be beneficial. But in the end, the proper way to clean any fuel injector is to remove it and even then you might still have to replace it if cleaning fails. If you are using a quality fuel injector cleaner, you might need to use a lot of those little bottles before the deposits break up.

decline fuel injector cleaning services

The next time you are in for automotive service and the shop tells you that you need your fuel injection system cleaned out, think about what that really means. Are you experiencing any problems, or is this one of those 'comparison' sales tactics where you are shown a before and after sample and advised that your system is just as dirty.

Chances are it's less about preventive maintenance and repair and more about losing $200-$300 to the shop. You'll probably hear this statement at an independent shop as opposed to a franchised dealer. In fact, it's a very popular upsell at smaller shops, in addition to fluid flushes. The truth is, most franchised dealers, which are the ones that sell new vehicles, do not offer this service and for very good reasons.

Manufacturers often advise dealers not to perform fuel injector cleaning

Many manufacturers are now instructing its dealers to not offer fuel injector cleaning or even the containers of cleaner to add to the gas tank. Prior to the mid 1990s, this type of service or product may have been beneficial to the proper operation of the vehicle. But today, it's just not necessary and can even do damage.

Removing components as part of 'routine' maintenance can cause unintended damage. Some of these chemicals can even damage fuel injectors and emissions components, such as oxygen sensors and catalytic converters. There's really no one verifying many of the statements on the product packaging. In fact, there's really no way to tell what's included in these cleaners without sending them off for lab testing.

fuel injector cleaning is not a part of most recommended service

Fuel systems are designed to remain closed, not to be opened up regularly. But they are also designed to be robust. Many vehicles even have fuel filters now that last the life of the car. Manufacturers don't list fuel filter replacement as a recommended service anymore and virtually none have ever recommended fuel injector cleaning, whether professionally or by adding a container to your fuel tank. The manufacturer will list certain procedures that you should regularly do. But if the manufacturer isn't requiring fuel system cleaning, you probably don't need it..

all gasoline has detergents that clean your system anyway

The Environmental Protection Agency (EPA) has required all gasoline sold in the United States since 1996 to have a minimum level of detergents to clean your system, so you're getting a fuel system cleaning already with every drop of gas that flows through your system. Top Tier gasoline and diesel fuel goes a step further. Top Tier is a standard applied to fuel that was developed by the major vehicle manufacturers to go beyond the minimum level of detergents mandated by the EPA, as well as to prohibit the use of metallic additives that can harm the emission system and fuel components. Top Tier gasoline typically contains about two to three times the amount of detergent compared to minimum EPA requirements and costs about an extra penny per gallon.

so, should you use fuel injector cleaner?

Just to put things into perspective: adding a small container of fuel injector cleaner to your gas tank is like adding a small amount of detergent to a full bathtub and draining it in the hope that it will clean the sewer lines. Those little bottles might help to clean out your fuel injectors and fuel system. Then again, they might not. We do know that modern gasoline will both clean your critical components and keep them clean. In fact, we visited a local salvage yard and disassembled a number of different components and found no significant buildups.

But if you are really worried, make sure you use Top Tier gasoline or diesel fuel, which is in use at nearly every major fuel supplier across the country.