The fuel system uses electro-hydraulic injectors, which are controlled by an electronic control module.
High pressure fuel is supplied to the injector from the rail.
A solenoid valve located at the top of the injector activates a needle that delivers the required amount of fuel through a nozzle to each cylinder.
Multiple fuel injection is carried out by the command of the electronic module (ECM), which controls the operation of the solenoid valves of the injectors.
The gaps in the nozzle nozzle openings are too small and any debris entering them will clog the nozzle.
Therefore, it is important to remove dirt around all fittings in the fuel system before servicing.
The high pressure fuel line fitting has a slotted filter that crushes small dirt particles that enter the fuel system.
It uses high-frequency fluctuations in fuel pressure to break down most of the particles to a size that matches the flow area of the injector.
All injectors are connected to a common low pressure fuel return line.
All excess fuel from the injectors, rail, and fuel pump is returned to the fuel tank through the low pressure fuel line.
A low pressure check valve is installed in the low pressure line, which prevents fuel from returning to the injectors along this circuit.
The drain lines are provided with push-type fittings with lynch clips on each nozzle.
If the injector is faulty or partially faulty, the engine will run unstable, consume more fuel, and the engine will "shake".
Fuel leakage through the drain line, as a result of a malfunction of any injector, can be checked as follows:
Disconnect the fuel drain line from each injector
Press on the latch fixing the drain pipe union
Disconnect the return line from the nozzle
We connect the separate drain hoses included in the nozzle leak test kit (catalog number 4918899).
If this kit is not available, suitable sized hoses can be used.
We lower all four hoses into separate measuring containers.
We start the engine and measure the amount of fuel collected per minute.
We compare the results for each injector.
The maximum fuel consumption for each injector should be 20 ml / min.
Removing the injectors
Do not remove the injectors unnecessarily!
Disconnect the negative terminal of the battery
We clean the area where the nozzle is located with compressed air or steam.
Press the latch and disconnect the wiring block from the injector
Press on the lock fastening the drain pipe fitting to the nozzle
Disconnect the pipeline from the nozzle
Unscrew the nut securing the high pressure pipe to the rail
Holding the nozzle fitting from turning, unscrew the nut securing the high pressure pipe to the nozzle
We pick up the phone
Unscrew the fastening bolt of the nozzle holder and take it out
Remove the nozzle holder
Remove the nozzle
Replace the copper O-ring of the nozzle body
To remove the nozzle, we slightly move it from its place and turn the nozzle by hand, gently swinging it in different directions.
If extra force is required to remove the nozzle, the tool (p / n 4919661) can be used.
Carefully insert the fixtures into the recess of the valve cover. In doing so, make sure that the two puller supports are located under the nozzle shoulder.
Apply a smooth vertical force to the body using the impact slider.
After removing the nozzle, put on the protective cover on the nozzle sprayer and mark the nozzle.
The body and nozzle of the nozzle should be cleaned in an ultrasonic bath using a safe water-based detergent.
Remove the protective cap from the injector nozzle.
Lower the nozzle vertically into the ultrasonic bath.
High pressure fuel line connectors and electrical connections must be protected from the ingress of detergent.
Check the nozzle tip for carbon deposits and corrosion.
Check the electrical connector for damage.
Contact resistance should be within 0.215 - 0.295 Ohm.
Record the setup code and installation location for each injector.
The customization code is a seven-digit alphanumeric code located on the top of the injector.
Before installing the nozzle, apply an anti-seize compound (catalog number 3824879) or its equivalent to the places of the nozzle where it touches the cylinder head.
When installing, use a copper sealing washer.
The sealing washer should be 1.5 ± 0.06 mm thick.
Only one copper sealing washer should be fitted to the nozzle.
The valve cover gasket should be lightly greased to facilitate the installation of the nozzle.
Loose tightening of the fuel supply line when connected to the injector will facilitate accurate injector positioning.
Install the bolt to secure the clamp and tighten the bolt. Tightening torque 15 Nm.
We pump over the power system and start the engine.
We check the tightness of all connections.