Replacing Fuel Injectors In A 1999 C230 Kompressor: Step-By-Step Guide

If you're experiencing problems with your 1999 C230 Kompressor's fuel injectors, it may be time to replace them. Fuel injectors regulate the amount of pressurised fuel used for each engine cycle, and when they fail or clog, engine power is reduced and misfires occur. Other symptoms of faulty fuel injectors include the check engine light turning on, the engine stalling, and the engine failing to start.

Replacing fuel injectors is not a DIY job and should be left to a professional, as it involves a large amount of labour and the risk of fire. The average cost for a Mercedes-Benz C230 Fuel Injector Replacement is between $1,637 and $1,927, with labour costs estimated between $1,109 and $1,398, and parts priced around $528.

You can purchase fuel injectors for the 1999 C230 Kompressor online, and there are also YouTube tutorials available that explain how to replace them.

Disconnect the electrical plug from the fuel pump unit

Disconnecting the electrical plug from the fuel pump unit is a crucial step in replacing the fuel level sender and fuel pump on a 1999 C230 Kompressor. Here is a detailed, step-by-step guide on how to perform this task safely and effectively:

Before beginning, ensure you have the necessary tools, which include a flathead screwdriver and a 7mm socket. It is also important to work in a well-ventilated area as the fuel tank will be open, releasing harmful fuel vapors.

First, gain access to the fuel level sender by removing the rear seat. Pop off the plastic covers from the seat bottom mounting nuts and then use a 13mm socket to remove the nuts. Pull the seat bottom away from the seat back and remove it from the car.

The fuel level sender is located under a black circular cover on the driver's side of the seat base. Use an 8mm socket to remove the six cover bolts. Remove the tan cover adjacent to the black cover to expose the fuel pump housing.

To relieve the fuel pressure, disconnect the electrical plug from the top of the fuel pump unit and start the car. Let the car run until it shuts off.

Return to the sending units and unplug all connections to the level sending unit. Remove the clamp from the locking ring using a 7mm socket and a flathead screwdriver to pry on the clamp. Spread the locking ring and pull it off the fuel pump assembly.

Partially pull the fuel pump assembly out of the tank. It will want to separate into two pieces. Disconnect the electrical connection from the top piece and remove it from the tank. Then, disconnect the three hoses and the remaining harness plug from the assembly. Push down on the button and push the third hose towards the connection before pulling it out.

With rags handy to catch any dripping fuel, carefully pull the assembly out of the tank. Fuel will remain in the assembly, so pour out as much as possible before removing it.

Now, focus on the fuel level sending unit. Use a flathead screwdriver or 7mm socket to loosen the clamp connecting the hose to the top of the unit. Place a rag under the hose connection to catch any fuel that spills out. Remove the lock ring's clamp and pull the assembly and hoses out of the tank.

At this point, you have successfully disconnected the electrical plug from the fuel pump unit and can proceed with the next steps of the fuel injector replacement process. Remember to work carefully and safely, especially when dealing with fuel, and always disconnect the battery to reduce the risk of fire.

Remove the fuel pump assembly

To remove the fuel pump assembly from your 1999 C230 Kompressor, you will first need to gain access to the fuel level sender. The fuel filter and level sending unit are located beneath the rear seat. Start by popping off the plastic covers from the seat bottom mounting nuts. Then, use a 13mm socket to remove the nuts. Pull the seat bottom away from the seat back and then out of the car.

The level sending unit is mounted under a black circular cover on the driver's side of the seat base. Use an 8mm socket to remove the six cover bolts. Then, remove the six bolts from the tan cover adjacent to the black cover to expose the fuel pump housing.

Before removing anything from the tank, you will need to relieve the fuel pressure. To do this, disconnect the electrical plug from the top of the fuel pump unit and start the car. Let the car run until it shuts off, then disconnect all connections to the level sending unit.

Next, remove the clamp from the locking ring of the fuel pump unit using a 7mm socket. Loosen the clamp enough to remove it, and use a flathead screwdriver to help pry it off if necessary. Spread the locking ring and pull it off the fuel pump assembly, then partially pull the fuel pump assembly out of the tank.

As you pull up the assembly, it will want to separate into two pieces. Disconnect the electrical connection from the top piece and then remove it from the tank. Next, disconnect the three hoses and the one remaining harness plug from the assembly. Two of the hoses will pull out, but for the third, push down on the button and push the hose towards the connection before pulling it out.

Carefully pull the assembly out of the tank, pouring out any remaining fuel. The assembly also has a fuel level arm attached, so be cautious as you remove it. Have rags on hand to catch any dripping fuel.

Disconnect the fuel injector from the fuel rail and electrical connector

To disconnect the fuel injector from the fuel rail and electrical connector, you will first need to gain access to the fuel injector. This will involve removing the intake manifold, which can be a large job that may include draining the coolant and oil, and removing several engine components.

Once you have access to the fuel injector, you will need to disconnect it from the fuel rail and electrical connector. Be sure to have a fire extinguisher nearby when working with fuel. To disconnect the fuel injector:

• Carefully release the fuel injector from the fuel rail by loosening any clamps or fittings that hold it in place. You may need to use a flathead screwdriver or a socket wrench to loosen the clamp.
• Once the fuel injector is free from the fuel rail, gently pull it out and place it in a safe place.
• Next, disconnect the electrical connector from the fuel injector. This will usually be a plug-and-socket connection that can be pulled apart by hand or with a small tool.
• With the fuel injector now disconnected from both the fuel rail and the electrical connector, you can set it aside and prepare to install the new one.

It is important to note that working with fuel can be dangerous, and it is recommended that fuel injector replacement be left to a professional.

Remove the intake manifold to access the fuel injectors

To replace the fuel injectors on a 1999 C230 Kompressor, you'll first need to remove the intake manifold to access the fuel injectors. Here's a step-by-step guide on how to do this:

Locate the intake manifold: The intake manifold is the part of the engine that supplies the air-fuel mixture to the cylinders. It is usually located on the top of the engine, between the cylinder head and the carburettor or fuel injection system.

Prepare the workspace: Park the car on a level surface and engage the parking brake. Make sure the engine is cool before starting work. Place a drain pan or container under the vehicle to catch any spilled fluids.

Disconnect the battery: Disconnect the negative battery terminal to prevent any accidental electrical shorts during the repair process.

Remove the air cleaner assembly: This will give you better access to the intake manifold. Remove the air duct work and any hoses or clamps connecting the air cleaner assembly to the manifold.

Locate and label the hoses and connectors: Before removing the intake manifold, carefully identify and label all the hoses, wires, and connectors attached to it. This will make it easier to reconnect everything properly later.

Disconnect the hoses and connectors: Using appropriate tools, carefully disconnect all the hoses, wires, and connectors from the intake manifold. Some hoses may be held in place with clamps or bolts, while others may be secured with quick-disconnect fittings.

Remove the intake manifold: Once all the hoses and connectors have been disconnected, carefully lift or slide the intake manifold out of its mounting position. Depending on the vehicle, there may be bolts or other fasteners holding the manifold in place that will need to be removed first.

Clean the mounting surface: With the intake manifold removed, take the opportunity to clean the mounting surface. Use a suitable solvent to remove any built-up grease, dirt, or debris.

At this point, you should have access to the fuel injectors and can proceed with the replacement process. Remember to install the new fuel injectors correctly, ensuring that all hoses and connectors are securely attached before starting the engine.

Install the new fuel injector

To install the new fuel injector, first prepare the new level sending assembly by slipping on the new seal and using zip-ties to secure the end of all the hoses together. Next, install the new unit by snaking the group of hoses along the front of the tank to reach the other side of the tank. Be careful not to damage the new level sender arm as you install the new assembly. Position the hoses from the level sending unit in the same way they were positioned before removing the old assembly, and then lock down the sending unit. Cut the zip-tie off the hoses as well.

Align the hose for the level-sending assembly with the nipple on the top of the assembly. Then, press the assembly into the tank. Slip the new lock ring onto the assembly and install the clamp around it. Use a 7mm socket to tighten the clamp. Then install the hose onto the top of the level sending unit.

Next, slide the bottom half of the fuel pump assembly into the tank and attach the hoses and electrical connections from the level sending unit. Then, place the new pump seal onto the tank and install the top portion of the fuel pump assembly.

Connect the electrical connection to the top of the assembly and then place the two pins with springs into the spots in the bottom half of the assembly. Press the top portion into the seal once the two halves of the assembly are appropriately aligned. Then install the new lock ring and clamp. Use a 7mm socket to tighten down the clamp.

Reconnect all of the electrical connections on the tops of both assemblies and start the car. Turn the key to the ignition on position before starting the car. Listen to hear the fuel system priming and then check for any leaks. If no leaks are present, start the car and take it for a test drive.

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