Professional Manufacture 0 445 120 126 Diesel Injector Common Rail Injector Engine Parts Vehicle Parts 0445120126

Daily inspection and basic maintenance
Appearance cleaning and status inspection
Check the outside of the injector regularly (recommended every 5,000 kilometers) to remove surface oil, carbon deposits and dust to prevent impurities from entering the fuel line.
Observe the connection between the injector and the cylinder head. If there is fuel leakage (such as wet marks), check whether the seal is aging and replace the oil-resistant rubber seal in time.
Check the injector harness plug to ensure that there is no looseness, corrosion or pin oxidation. If necessary, wipe it with a special cleaner and apply conductive paste.
Fuel system cleaning
Use high-quality fuel: Poor-quality fuel contains impurities such as sulfur and colloid, which can easily cause the injector nozzle to be blocked or worn. It is recommended to choose fuel that meets the grade (such as National VI standard diesel/gasoline) from regular gas stations.
Regularly replace the fuel filter: replace it according to the requirements of the vehicle manual (usually 20,000-40,000 kilometers) to prevent impurities from entering the injector after the filter is blocked.
Add fuel system cleaner: Add special cleaner (such as polyetheramine) every 10,000-20,000 kilometers to dissolve carbon deposits on the injector nozzle and maintain the spray effect.

Performance test and parameter calibration
Injector working status test
Auscultation method: Start the engine and use a stethoscope to listen to the working sound of each cylinder injector. Normally, it should be a uniform "click" sound. If the sound of a cylinder is abnormal (too weak or no sound), the injector may be stuck or blocked.
Cylinder disconnection test: Disconnect the wiring harness plugs of each cylinder injector in turn at idle speed and observe the changes in engine speed. If the speed does not drop significantly after disconnecting a cylinder, it means that the injector of the cylinder is not working properly.
Professional equipment detection
Go to the repair shop to use the injector tester to test the following parameters:
Injection pressure: Deviating from the standard value (such as 180-200MPa for diesel vehicles) will cause poor atomization, and the pressure regulating spring needs to be adjusted or replaced.
Spray state: Normally, it should be fine mist and evenly distributed. If oil droplets or spray deflection occur, the injector needs to be disassembled, cleaned or replaced.
Oil return volume: The oil return volume of a single cylinder at idle speed should be less than 5mL/min (refer to the specific vehicle model). Excessive oil return may be caused by poor needle valve sealing.
Electronic control part inspection
For electronic control injectors (such as common rail systems), use a diagnostic instrument to read the injector drive current, injection pulse width and other data streams to determine whether the solenoid valve/piezoelectric crystal is normal.
Measure the resistance of the injector coil (usually 2-3Ω for low resistance type and 12-15Ω for high resistance type). Abnormal resistance indicates that the coil is short-circuited or open-circuited.

Fault repair and maintenance operations
Carbon deposit cleaning
Mild carbon deposits: Use an ultrasonic cleaner (with a special cleaning agent) to clean the injector nozzle and needle valve parts to remove carbon deposits and colloid.
Severe carbon deposits: Disassemble the injector and clean the injection hole with a fine wire brush (be careful to avoid scratching the hole wall). After cleaning, the spray state needs to be re-tested.
Replacement of seals
After each disassembly of the injector, all seals (such as O-rings and copper gaskets) must be replaced to avoid fuel leakage or air intake due to poor sealing.
Tighten according to the specified torque during installation (usually 20-30N・m). Too loose will easily leak, and too tight may damage the housing.
Replacement of worn parts
If the needle valve and valve seat are worn and the injection hole is deformed, the injection pressure will drop and the atomization will be poor. The needle valve pair or the entire injector needs to be replaced (some models do not support the replacement of pairs separately).
When the piezoelectric crystal or solenoid valve fails, the corresponding electronic control components need to be replaced to ensure accurate injection timing.

Precautions for long-term use
Avoid inferior fuel: Long-term use of low-grade or impurity-exceeding fuel will accelerate the wear and blockage of the injector nozzle. It is recommended to perform a comprehensive cleaning of the fuel system every six months.
Check the fuel pressure regularly: Insufficient fuel pump pressure will cause unstable fuel supply to the injector, and the fuel pump (such as SCV valve and high-pressure pump) needs to be maintained simultaneously.
Cold start protection: Preheat the engine (especially diesel vehicles) before starting in winter to avoid wear of the injector due to insufficient lubrication in the cold state.
Timely troubleshooting: If the engine power drops, the idle speed shakes, and the emission exceeds the standard (black smoke/blue smoke), the injector needs to be checked immediately to avoid the expansion of the fault (such as stuck and causing lack of oil in the cylinder and cylinder pull).