Electronic fuel injection service & repairs

At Hitech Auto Electrical and Mechanical Service we can service all your Electronic Fuel Injector needs. Don’t buy new until you have yours tested on our Programmable Test Stand. We can also Ultrasonically Clean, Flow Match, Leak Check, and Repair your injectors.

Since your car was new, dirt, varnishes, and carbon deposits have been forming in your vehicle’s fuel system, on the intake valves and in the combustion areas. These build-ups can rob your car of performance.

    GENERAL ENQUIRE

    Electronic fuel injection service & repair

    Some of the symptoms related to carbon build-up are engine pinging, hesitation, poor acceleration, lack of power, repeated stalling when cold, poor performance when cold, rough idle, and poor fuel economy. These build-ups, if left untreated may lead to costly engine repairs. Our Carbon Cleaning System is a revolutionary new process that will clean your vehicle’s fuel system, including injectors, and remove harmful carbon deposits. This system utilises a unique cleaning solution which will not damage your vehicle’s sophisticated engine components.

    We offer and specialise in the following efi services

    ELECTRONIC FUEL INJECTION
    • Traditional & Electronic EFI systems
    • Engine management
    • Fuel injector testing & repair
    • Engine Diagnosis and repairs
    • Ultrasonic cleaning and back flushing
    • Flow testing (volumetric and timed)
    • Fuel injection pump testing & repairs
    • Emissions testing
    • Servicing & general maintenance & repairs (All makes and models)

    Injector balance

    To achieve smooth engine running and optimum performance , the amount of fuel flowing through each injector on a multi point fuel injection system needs to be balanced.

    Injector flow bench testing

    Flow bench testing of injectors requires them to be removed from the engine. The removed injectors are set up in the test bench and supplied with a fuel substitute test fluid. The electronic injectors are connected to a controlled power source and pulsed as they would be in the engine. The fuel flow from each injector is collected in a measuring tube and compared to other injectors from the set and against calibration specifications. The spray pattern from each injector nozzle is checked. Defective injectors can be identified, cleaned, repaired or renewed.

    Types of electronic fuel injection

    Multipoint injection system: (MPI)

    A multipoint injection system consists of at least one injector per engine cylinder. Fuel flow through each injector should be balanced. Sequential fuel injection systems may use a camshaft position sensor to determine firing cylinder order.
    Single point fuel injection Single point injection system : (SPI) sometimes referred to as centre point injection or throttle body injection. Fuel is injected into the throttle body at a single point before the throttle valve where maximum air flow occurs. This system looks very similar to a carburettor with electronic control.
    OUR EFI SERVICES INCLUDE THE FOLLOWING
    INJECTION PRESSURE TESTING Fuel injection fluid pressure is generated by a fuel pump. Fuel for combustion is delivered via fuel lines to the injectors. The fuel pressure is controlled by allowing a certain amount of fuel to be returned to the fuel tank via a pressure regulator. Higher pressure allows better atomisation of fuel. Fuel pressure faults can be caused by restricted fuel lines, system leaks, blocked filter, defective pump, defective fuel pressure regulator. fuel-injectors1

    Fuel flow testing

    Fuel-System-Injector

    Fuel flow requires pressure

    The amount of fuel flow available will determine the amount available for injection. Fuel flow could also be controlled by fuel pump rotor speed. Restrictions in fuel flow can be caused by eg, blockages in fuel lines, blocked fuel filter, defective fuel pump, etc. Injection duration This is the amount of time during the injection cycle that fuel flows from the injector nozzle. The longer the injector opening time the greater the quantity of fuel flowed through the injector nozzle. Modern fuel injection systems achieve closed loop control when the engine reaches normal operating temperature by measuring the quantity of oxygen (burnt as the fuel is combusted) in the exhaust gas.

    Injector flow bench teting

    Flow bench testing of injectors requires them to be removed from the engine. The removed injectors are set up in the test bench and supplied with a fuel substitute test fluid. The electronic injectors are connected to a controlled power source and pulsed as they would be in the engine. The fuel flow from each injector is collected in a measuring tube and compared to other injectors from the set and against calibration specifications. The spray pattern from each injector nozzle is checked. Defective injectors can be identified, cleaned, repaired or renewed.

    What faults are caused by defective injectors?

    Fuel injectors with a defective spray pattern causing poor atomisation which may result in ‘flooding’, excessive fuel consumption and high exhaust CO emission. Blocked fuel injectors can result in incorrect fuelling leading to an excessively lean mixture. A lean fuel mixture requires a higher spark kV to ignite the mixture leading to problems with ignition systems / coil packs etc , overheating, and damaged valves.

    How are injectors cleaned?

    Once removed from the engine , Injectors may be cleaned ultrasonically to remove dirt contamination and lacquer deposits. The filters can be replaced and if required new nozzle etc, fitted to the defective injector. Injectors can then be rechecked on the flow bench to ensure they meet performance specification . Injector servicing should increase performance and fuel economy.

    Why do injectors deteriorate?

    Fuels contain chemicals which can form lacquer ( or varnish ) , over periods of time this lacquer builds up and clogs the very fine holes in injector nozzles and can stop the needle valves from seating properly resulting in blockages and deterioration of the spray pattern. Dirt contamination in the fuel system can also cause blockage.. Condensation in fuel tanks can introduce moisture into the fuel system which can cause rust resulting in nozzle deterioration.