Mercedes-Benz 500SEC Fuel Pump Replacement Cost
How Much Does a Fuel Pump Replacement Cost?
Fuel Pump Replacement Service and Cost
The fuel pump's main responsibility is to deliver fuel from the fuel tank to the fuel injectors. The pump must deliver the appropriate amount of fuel and at a high enough pressure to provide the engine adequate fuel in all conditions.
Fuel pumps on a majority of automobiles use an electric motor which drives a fluid pump. The pump can be located inside or outside the fuel tank. In both cases the fuel is sucked out of the fuel tank and pushed through a fuel line to the fuel filter, then to the fuel injectors.
The fuel pump can fail in a few ways. 1. Engine will not start: In this case you will need to get it replaced to be able to drive the car. 2. Engine stalls or will shut off while driving: Continuing to drive with these symptoms can put you in a dangerous situation where the car stalls in traffic, putting you in a potentially dangerous situation. In this scenario the vehicle may be restarted and can be driven, but we recommend you only drive far enough to get to a safe place then have the car towed to a repair shop. 3. Car lacks power: This is similar to the above scenario where you may be putting yourself in a risky situation and we recommend driving just enough to get to a safe place, then get the fuel pump repaired.
Fuel pumps do not have a specific replacement interval. However, the fuel pump is running the entire time the engine is running, so replacement becomes more common as mileage increases. Running the tank low, or clogged fuel filters can put additional strain on the fuel pump, shortening its life expectancy.
Fuel Pump Replacement Repair Information
If the engine will not start, the mechanic will check for fuel pressure at the fuel injectors when trying to start the car. If fuel pressure is sufficient according to the manufacturer's specification, then they will check that the pump is delivering adequate volume of fuel. If the pressure is low or nonexistent, then next step is to check the electrical circuit for the fuel pump. If the pump is does not receive adequate voltage or has a bad ground connection, the fuel pump is not the problem and they will diagnose the electrical circuit. When the pump is working but is providing low pressure or low volume output the mechanic will check the fuel filter, and the electrical and mechanical condition of the fuel pump itself.
In all cases, before opening the fuel system the mechanic will disconnect the battery to ensure no possibility of a fire. When a fuel pump is located in the fuel tank, there will usually be an access cover that needs to be removed to access the pump. Once this is removed you can replace the pump and pre-pump filter screen. In some cases fuel will need to be drained before removing the access panel. When the pump is externally mounted the mechanic will disconnect the fuel lines, remove the pump and install the new one. Once the pump is replaced they will recheck to ensure there are no fuel leaks and that the original customer complaints have been remedied.
Repairpal recommends that the fuel filters are replaced at the same time the fuel pump is replaced. This applies to the intake screen for in-tank fuel pumps as well. On some vehicles the fuel pump relays are known to fail and on these vehicles it's a good practice to replace the relay when the pump is replaced.
Any time you are working with a fuel system you have to be 100% certain you are taking the proper precautions to prevent fuel spills or the possibility of igniting the fuel and causing a fire. After the repair is performed be on the lookout for fuel leaks or fuel odors. If you see or smell fuel do not start or drive the car, and do not park inside your house or any covered structure. Have the car towed to a shop for inspection and repair. Failure to perform a proper diagnosis is where people often pay more than they need to. Since it's possible a clogged fuel filter or problems with the electrical system powering the fuel pump can result in symptoms similar to a failed fuel pump, be sure to have your repair shop verify that the pump is the problem before replacing.
Some fuel pumps are fairly easy to replace and some very difficult. Since there is a risk of fuel leaks and a potential for fire, we recommend only advanced do-it-yourselfers tackle this job, or professional repair shops. Inexperienced people can make a mess of this job by misdiagnosing the problem, damaging fuel line connections and causing fuel leaks. Unless you are very experienced, leave this one to the professionals.