Injectors test and replacement

If your engine fault LED remains on, or if your vehicle makes this noise, or if your vehicle does not start, you may have an injection problem. Check that the high-pressure fuel pump supplies fuel to the injectors. Loosen the high-pressure pipe unions one half of a turn. Activate the starter. Tighten the pipe unions through which the diesel flows. Activate the starter. The high-pressure fuel pump supplies fuel to the four injectors. Try to start the engine with brake cleaner. Spray brake cleaner into the air filter intake for about one second. Start the engine immediately and without preheating the plugs. If the engine starts with the brake cleaner, it is most likely a fuel injection issue. White smoke typically means a worn-out injector. Engine vibration at idle means a combustion issue in one or more cylinders. An injector return flow test can detect any leaks inside the injectors. Disconnect the fuel return pipes. The injectors are interconnected by small hoses, which return unused fuel to the tank. The return volume is proportional to the leaks inside the injector. Place a plug on the connector of the high-pressure pump fuel return pipe. Connect four hoses of the same diameter. Use fuel return pipe, aquarium hose, or windshield washer hose to the injectors. Insert these hoses in an empty bottle. Start the engine. The containers are filling with fuel. The injector number one has a high return flow. The injector number two has a very high return flow. The injector number three has an even higher return flow. It flows almost continuously. The injector number four has a high return flow. After five minutes, the return volume of injectors two and three is more than the two others. They must be replaced first. Warning, if you have one injector without any flow return, either the electronic control of the injector is defective, no fuel flow into the injector, or the injector is stuck in open position and in this case, do not drive anymore with your vehicle because the excess of fuel in the cylinder may burn the piston. Before replacing the injectors, make sure that your fuel system is not contaminated with metal filings. Place a container under the fuel filter and unscrew the bleed screw. If your high-pressure pump is very warm, it can generate metal filings that clog your injectors. If you replace the injectors and your pump continues to generate metal filings, you will destroy your new injectors with the small metal particles it produces. If you find filings, replace the pump and clean the entire fuel system, including tank and which flows back injectors, and change the injectors. There are some black particles but no presence of metal filings. Bright yellow metal particles. Refit the bleed screw and prime the low-pressure circuit by operating the primering bulb. Blow around the injectors with compressed air. Disconnect the injector connectors with a needle-nose pliers. Unclip the clip between the high-pressure tubes. Remove the high-pressure pipes. Remove the injector brackets with a Torx bit. Remove the injectors by rotating them while pulling them upwards. If the injector is stuck in its well, you can use releasing spray to remove it. Take back the far-resistant washers if they remained in the well. Block the opening with a Phillips screwdriver and blow to remove impurities. Clean the injector well with a microfiber lint-free. Note the reference of the defective injectors and replace them with new ones or fully refurbished. Often cheaper with the same guarantee, here are the two replacement injectors. One new and one fully refurbished. Internet purchase. Note on the paper the 16 digits found on injector head. This code can be programmed into the memory of the ECU with a diagnostic tool for optimal operation of the injection. Refit the new injectors with a new seal. Refit the injector brackets. Tighten to torque. Refit the high-pressure pipes. The seller of the injectors and the technical review advocate the systematic replacement of the high-pressure pipes. It is written, make sure to change the HP pipes. In case of any doubt, do not hesitate to drain the tank. In the event of a warranty, proof of purchase of the HP pipes may be required. It's up to you whether you need to change your HP pipes or not. If you choose to refit the old HP pipes, spray brake cleaner and blow compressed air inside pipes. Reconnect the electric connectors. Reconnect the fuel return pipes. Prime the low-pressure circuit by operating the prime airing bulb. Start the engine. Engine vibration at idle disappeared. The exhaust fumes disappeared. A new injector return flow test will confirm the repair. The injector number 1 still has a high return flow. The new injector number 2 return flow is very low. The return flow of a new injector drips. The new injector number 3 return flow is very low. The injector number 4 still has a high return flow. After 6 minutes, the new injectors 2 and 3 are OK. Their return volume is very low. Injectors 1 and 4 have 250,000 km. Their return volume is more important. The vehicle regained normal operation with the change of 2 injectors out of 4.