The last time you were at an auto repair shop you may have been offered an EFI service. If you don’t have a trusting relationship with your auto shop, you may feel like they were trying to sell you snake oil. Let’s look at what EFI is and why these services are essential to keeping a healthy engine.
First, what is EFI? EFI stands for Electronically controlled Fuel System. This system is responsible for delivering gasoline from a vehicle’s fuel tank to the engine’s combustion chamber in the proper amount and at the proper time. Unlike older fuel systems that used mechanical devices to deliver fuel, electronic controlled systems use sensors to gather information and deliver it to the engine control module. This module then commands fuel injectors to operate, thereby delivering fuel to the engine. Today’s engines use two different types of EFI systems, Multi-Port Injection (MPI) and Gasoline Direct Injection (GDI).
Multi-Port Fuel Injection engines have been around for a while. There is one fuel injector per engine cylinder. Fuel is injected as a mist into the intake manifold side of the engine’s intake valve. When multi-port injection was introduced, it greatly increased efficiency, reliability, and engine performance.
Gasoline Direct Injection engines are the newest form of electronically controlled fuel systems. They also have one fuel injector for each engine cylinder. However, unlike MPI, fuel bypasses the intake manifold and is injected directly into the engine’s combustion chamber at a very high pressure. The high pressure of the system allows the fuel to atomize, providing a cleaner and more efficient combustion than the older MPI systems could provide.
Both fuel systems have pros and cons. Several manufacturers have even started combining both fuel systems on a single engine to utilize the efficiency and performance benefits that each has to offer. One thing both fuel systems have in common is the need for regular maintenance. EFI service kits come in a few different configurations based on specific fuel system requirements, but the result after performing the service is the same. A combustible cleaner is injected into the engine, either through the intake manifold or through the fuel injectors with the engine running. EFI services are designed to be a preventative service. If performed regularly, every 15,000 miles, it will keep the carbon and soot from building up in the first place. If a problem occurs due to lack of service, too much soot and carbon may be present for this service to help, and more extensive repairs would be needed.
Under normal operation, carbon and soot will build up on an engine’s throttle plates, intake manifold, intake valves, and multi-port fuel injector nozzles. If left unchecked, excessive build up can cause many different types of engine performance issues that would cause the check engine light to illuminate. Cleaning off this build-up will help the engine computer properly calculate the amount of air being brought into the engine and ensure the fuel injector nozzle is clean and able to provide a mist of fuel vapor for even combustion. In the case of the GDI system, it is very important that the intake valves are regularly cleaned. Unlike an MPI system, fuel does not pass the intake valve which would help reduce build up. Unless it is cleaned manually, carbon and soot will continue collecting on the intake valve until a mechanical failure occurs. Inside the combustion chamber there can be soot and carbon deposits as well. This would also be removed when performing a regular EFI service. Once the cleaner has combusted and entered the exhaust system it continues removing soot from oxygen sensors and helps burn off excess soot caught in the catalytic converters. This allows the oxygen sensors to communicate more accurate exhaust gas content information to the engine computer and, at the same time, extends the life of the catalytic converters by helping to keep them free from clogs.
EFI systems are complex but very reliable in today’s vehicles. Regular service can eliminate long-term problems before they begin. BG Products such as 44k and Air Intake Valve & Combustion Chamber Cleaner are commercial grade service products that are used at dealerships and professional repair centers across the country. Ask for their products and “Lifetime Warranty” information at professional repair shops like Dripping Springs Automotive.
For more information go to www.drippingspringsauto.com and look for BG products under the “Services” tab.