Fuel-System Maintenance is Essential in Modern Engines

It used to be common practice for vehicle owners to spend a Saturday afternoon in the garage, giving their vehicles a tune-up. There was a sense of pride and accomplishment in working under the hood, getting their hands dirty and knowing the efforts would help keep the car or truck running strong. Back then, vehicles were much easier to work on – the engine layouts were open, components were accessible and the average Joe didn’t need advanced training or complicated tools to perform maintenance.

Today’s vehicles are a different breed. The push for better fuel economy has led to smaller engines littered with computerized monitoring systems and complex technologies all tightly packaged together. As a result, most of us are taking our vehicles to repair shops for even the most routine maintenance. Yet all vehicle owners can still perform a quick engine “tune-up” with no tools or automotive background required. Instead of turning wrenches, it comes in the form of a fuel additive.

As you know, motor oils are tasked with several functions beyond just lubricating, including keeping engine components clean. This is made possible by the use of detergent and dispersant additives. Their role is to prevent contaminants from sticking to engine components, especially hot components such as pistons and rings. However, motor oil is not able to prevent deposit build-up on certain components, including fuel injectors, intake valves and combustion chambers. That’s where boosting the cleaning power of gasoline comes into play.

Fuel injectors are traditionally located in the air intake ports, and they spray fuel in a fine mist that mixes with air as it passes by the backs of the intake valves. Fuel injectors of this style are appropriately called port fuel injectors. Port fuel injectors become clogged with deposits over time, which causes that fine mist of fuel to turn into an unpredictable stream of fuel. As a result, the fuel doesn’t mix as well with the air, and the combustion of the mixture is less effective.

Now consider a gasoline direct-inject engine such as the Ford* EcoBoost* or GM* Ecotec,* which have fuel injectors positioned with the tip located inside the combustion chamber. Because of this location advantage, they can better control the spray of finely atomized fuel into the cylinders, leading to increased power, reduced emissions and most importantly these days, improved fuel economy. During normal engine operation these injectors are exposed to much higher temperatures and pressures, which leads to more rapid deposit build-up than the build-up on traditional port fuel injectors. The outcome of plugged injectors is the same – poor spray patterns causing lost power and efficiency.

In a port fuel-injected engine, the next components that can be reached through the fuel system are the intake valves. Their job is to allow air into the combustion chamber at the precise time that it is needed, then close tightly to seal the chamber during combustion. The valves tend to accumulate deposits over time that can prevent them from sealing properly, allowing pressure loss and poor engine performance. Since the port fuel injectors are positioned to spray at the valves, any deposits that form on them can be easily addressed through fuel additives. However, in direct-inject engines the intake valves never get fuel sprayed on them, so fuel additives have a minimal effect on cleaning those deposits.

The final components that see a significant benefit from fuel additives are the components that form the combustion chamber itself: the piston, cylinder walls and head. The extreme temperatures and pressures they are routinely exposed to make them prone to deposit formation. These deposits can lead to hot spots that cause the air-fuel mixture to ignite before it should, resulting in uncontrolled combustion known as engine knock. Today’s engines have sensors to detect that condition, and they constantly make adjustments to compensate. The good news is that those adjustments prevent the knock from causing significant engine damage. The bad news is that the engine is no longer operating at its most efficient settings, leading to lost power and fuel economy.

This is where quality fuel additives make a difference. Their role is to clean the deposits that the motor oil cannot reach. AMSOIL P.i.^® Performance Improver is a highly concentrated formulation specifically designed to clean all of the deposits previously mentioned. In fact, P.i. cleans your entire fuel system and restores up to 14% horsepower¹ in one tank of gasoline. The result is restoring and maintaining engine performance. No wrench-turning required.

¹Based on third-party testing in a 2016 Chevrolet* Silverado* 1500, 5.3L V-8 GDI with 100,616 miles, using one tank treated with AMSOIL P.i. Actual results may vary.

*All trademarked names and images are the property of their respective owners and may be registered marks in some countries. No affiliation or endorsement claim, express or implied, is intended by their use.