Complete Fuel Injection Service
What is a Complete Fuel Injection Service?
The SelTec® Complete Fuel Injection Service is a complete upper engine induction cleaning. Some people refer to this procedure as a flush, purge, or de-carbonization. The SelTec® Complete Fuel Injection service is effective at helping vehicles pass emission standard testing, so it can also be referred to as an Emission Service.
What is the procedure?
The SelTec® Complete Fuel Injection Kit contains 3 parts, including the SelTec® Fuel System Cleaner that is installed into the tank. This provides all of the benefits laid out in the previous section on Fuel System Service, such as removing water and cleaning fuel injectors.
The first step in this procedure is to install the tank additive. The second step is to clean the throttle body and air intake system with the one-job size can of high quality air intake cleaner. It is effective at removing deposits from the throttle plates, throttle body, plenum, manifold, and is safe on all sensors including the IAC (Idle Air Control) valve.
Why do we need to clean the air intake system?
Another design change that resulted from downsizing these fuel-injected engines to meet EPA specifications is that we no longer vent exhaust gases to the atmosphere. Today’s fuel injected engines now have an EGR (Exhaust Gas Re-circulation) valve, which does exactly what it says. We are re-circulating (recycling) exhaust gases that previously were vented to the atmosphere, back through the engine to be re-burned. By re-burning these exhaust gases we reduce emissions and generate better fuel economy and engine efficiency. The only problem is that they also create substantial deposits in the air intake system. The EGR will create deposits in some engines as early as 2,000 miles. These deposits are typically soft (some are hard) hydrocarbon deposits from both oil and fuel. The deposits cling to all the surfaces throughout the air induction system, such as the throttle plates, plenum, manifold, runners, and sensors. The impact these deposits have on engine efficiency is that they impede airflow and degrade both fuel economy and drive-ability.
Volumetric efficiency is the maximum amount of airflow through the air intake system to feed the combustion chamber. When an engine is new and the air intake system is clean, it functions at the optimum level of volumetric efficiency. Engineers go to great lengths to design manifolds and runners to optimize volumetric efficiency. Even the untrained eye can notice the aerodynamic design of the manifolds on these new high-tech engines. Cleaning the air intake system is an important part of the SelTec® Complete Fuel Injection Service.
Spraying down the air intake system prior to drawing the SelTec® Combustion Chamber Cleaner through, helps by cleaning most of the deposits in the plenum, and softening the rest, so that the Combustion Chamber Cleaner can finish the job as it is drawn through a vacuum source near the throttle plates. This method does a double cleaning of the air intake system, improving volumetric efficiency and overall engine performance.
We recommend that the Air intake cleaner be sprayed into the throttle plate area while the engine is not running, so that you can open up the throttle plate to get behind it. Then start the engine and run the remainder of the can in through the throttle plate while the engine is running. This is important because the engine must be running to get the product into the IAC valve.
This product is safe on all sensors. If there is a MAF (Mass Airflow Sensor) up-line from the throttle plate, then the engine may not want to run with the boot off the air intake system. In this case you have no choice but to run the whole can in with the engine off.
The third step of the SelTec® Complete Fuel Injection Service is to install the SelTec® Combustion Chamber Cleaner through a vacuum source at 2500 rpm. Drawing the chemical through the air intake at the throttle body is important to clean all areas of the manifold and the
secondary throttle plate located in the manifold that some vehicles are equipped with. This secondary throttle plate is designed to open up at high rpm, such as when you step on the gas to pass a vehicle, to give increased power when needed, and to conserve energy and fuel at lower rpm’s. Technicians are finding that when the secondary throttle plate is not used frequently it tends to gum-up with the same soft deposits that are created by the EGR in the manifold area. It can become sticky to the point where it will not work properly when needed, having a negative impact on drive-ability. With dramatic improvements in injectors we are finding that they are virtually deposit free – the majority of deposits impacting drive-ability are coming from EGR deposits throughout the air intake system, combustion chamber and intake valve deposits.