Everyday driving is slowly taking its toll on your vehicle and all of the components associated with it. Your Fuel Injection System is no different! Majority of people will fill their Vehicle with fuel on a weekly basis especially living on the Gold Coast, and unfortunately Fuel is not 100% clean from contaminants, therefore overtime these contaminants will build up and affect the overall health of your Fuel Injection System.
Fuel Filters should always be replaced in regards to the Dealers Service Schedule or if not sooner to help lengthen the life of your Fuel Injection System. As the Contaminants begin to build up they will slowly block the Fuel filter and restrict the amount of fuel supplied to the engine. As well as this, small particles can often bypass the filter and make its way through to the Fuel Injectors. When these contaminants build up in the Fuel Injectors they will begin to change the overall Spray pattern of the Injector resulting in reduced economy, and even in some more severe cases cause the Fuel Injector to Leak causing symptoms such as:
- Vehicle being hard to start
- Running Poor At Idle
- Misfiring under load
Majority of Fuel Filters are a simple job to replace as they are either located underneath the vehicle or inside the engine bay. Alternatively there are Fuel Filters that are located inside the tank which are more time consuming to replace.
When replacing Fuel Filters on Diesel Vehicles, It is extremely Important that the Filter is changed in relation to the Dealers Service Schedule or Every Service, this is because contamination of the diesel system can become a very costly repair! By replacing a Fuel Filter Every Service we consider this to be cheap insurance to help reduce the possibility of any costly repairs. As well as replacing the fuel filter we also suggest that Fuel Injection Cleaner be added to your Fuel Tank once every month to help remove any harmful build up in the Injectors and Fuel System.
The evolution of Fuel Injection
The supply of fuel to a motor vehicle engine has been traditionally for the first half of the 20th century been through the use of a carburettor or traditionally known as “carby”. These have changed as time went on from the extremely basic venturi style with two jets which would have been fitted to vehicles such as the model “T’ fords, to the end of the century with Holley four barrel with either vacuum or manual secondary’s to help increase performance abilities
In the latter half of the century fuel injection systems were introduced in the mechanical form where a nominal fuel pump would deliver fuel to a mechanically timed injection pump already pre-set to deliver a predetermined amount of fuel to the engine. This was a revolutionary step forward and is necessary in the diesel engine world but for petrol engines a new thing. This type of injection had its failings because whether under acceleration or de acceleration the pump would deliver fuel to the engine causing fuel to be burnt under no load.
Fuel injection then started to change rapidly with timed electronic injection to computer controlled injection and now what is called “common rail injection” where the fuel pressures are extremely high to produce a more atomised and economical mixture to the engine. As well as using extremely high pressures there are also several sensors fitted to the engine to send signals back to the computers Engine Control Unit – Also known as an ECU – in order to ensure the engine is always getting the desired amount of fuel and maximise the efficiency of the engine.
Benefits of Fuel Injection
There are many different benefits of Fuel Injection as appose to the older Carburettor Style.
- The ability to inject fuel as close as possible or even in directly into the combustion chamber for the best possible combustion of the fuel.
- Increased Vehicle Economy.
- Increased Responsiveness from the Engine when power is demanded.
- Ease of starting the vehicle in all temperature ranges as appose to Carburettors.
- Reduced Emissions as a result of a cleaner combustion process.
As the Fuel Injection System has been developed and also the vehicles electronics have improved it has been made possible to determine the exact time in which each cylinder in your engine requires fuel. Through the use of Cam and Crank Angle Sensors and Knock Sensors which are fitted to almost every modern engine it is possible to determine exactly the position of each piston inside of the engine, and therefore Inject the correct amount of fuel for the power demand at exactly the right time to ensure the engine is always running as efficiently as possible.
Different Components of a Fuel Injection System
Fuel injectors – There are several different types and styles of Fuel Injectors depending on the application. In Most Petrol Vehicles your Fuel Injectors are mounted in a fuel rail on the inlet manifold as close as possible to the combustion chamber. Fuel is constantly being fed into the rail and as the ECU Sends the Signal to the Injector it then opens for the desired time and injects the required amount of fuel before the injector then closes stopping fuel from entering that cylinder until opened again.
Fuel Pressure Regulator/Pressure relief valve – The Fuel Pressure Regulator/ Pressure Relief Valve is responsible for controlling the pressure in the fuel System and ensuring that excessive pressures are not reached by the Fuel Pump. In Petrol Vehicles this is located in either the fuel rail or on a non-return system in the Fuel Filter Assembly inside of the Tank. On Diesel Vehicles you will find the Pressure Relief Valve on the Rear of the Diesel Pump.
Fuel filters – Fuel Filters are extremely important components to help ensure the maximum life span of your Fuel System. The filter is designed to capture any contaminants such as dirt and grime and even water. In a Diesel System Fuel Filters can mean the difference between keeping your vehicle running nicely and an expensive repair. When Diesel Fuel is contaminated it can cause severe damage to the Injectors and Fuel Pump which can prove quite costly to repair.
Supply and return lines – These are the lines in which the fuel is carried from the tank through to the engine. Generally made out of an aluminium line and mounted underneath the vehicle with joiners fitted to allow the fitment of Fuel Filters and Flexible Hoses.
Fuel pump – The Fuel Pump is what Pumps the Fuel from the Tank through to the engine, On Petrol Vehicles this is mounted inside of the tank and inside of a swirl pot to ensure that the Pump is always immersed in fuel and will not run dry while cornering or under heavy braking. Different Fuel Pumps can supply different volumes of fuel depending on the engines demands. There are also aftermarket and performance applications readily available for many different Vehicles
Fuel tank – The Fuel tank is mounted underneath the Vehicle and is obviously responsible for storing the fuel.