Hello house, I changed my fuel golf3 fuel pump and I took it for a test drive. Not quite long after that, I was hearing a buzzing sound at the back where the fuel pump is located like a big housefly is gallivanting on a window screen. I had to have them change the fuel pump again and the sound stopped and after another test drive it started again. What could be the issue? I've searched online and I was getting different views on it. Some say its bad, some say its okay and what have you. I want to get advices from the auto guys here before I call the person who fixed it for me. Thanks.

There are several possible causes for this
problem.
1. Low Fuel
Fuel pumps work by pressurizing the fuel
and sending it to the engine. A low fuel
level can cause the engine to work much
harder to build the necessary pressure to
pump the fuel. To analyze the problem,
start the car when the fuel is low (below
one-fourth tank) and listen for the sound.
If the whine is audible, fill the tank
immediately. When you start the vehicle
again, the whine should be reduced or
absent. If not, there may be another
problem.
2. Damaged Pump
The whining noise may be caused by a
damaged fuel pump. The fuel pump may
be punctured or dented, reducing its
efficiency. To resolve this issue, the fuel
tank must be accessed and repaired or
removed. The location of the fuel tank
depends on the construction of the
vehicle. In a vehicle equipped with a
carburetor, the fuel pump is often located
outside of the fuel tank. With a vehicle
that has a fuel injector, the fuel pump is
located inside of the tank. It is best to get
a mechanic to address this problem.
3. Impurities in Gas Tank and Engine
If the fuel pump is blocked by engine
gunk, dirt, impurities in the gasoline or
anything else, it will respond with a
whine or some other very noticeable
noise. Debris in the fuel tank can be
sucked into the pump most easily when
the tank is low. This debris gets caught in
the pump and reduces the pressure. This
problem must be fixed by removing the
blockage which should be performed by
a mechanic. Using fuel additives that
clean the engine and keeping the fuel
tank filled may also be a preventative
measure.
4. Other Damaged Parts
A whining fuel pump may also be a sign
that other parts of the car are damaged. If
a hose that transfers fuel to the engine or
carburetor is damaged, it will release air
into the fuel system and reduce the
pumping pressure, resulting in the noise.
If a connection is loose between the fuel
pump and any other part, the same result
may occur. The vehicle should be
examined by a professional who can
pinpoint the damage and make repairs.

^^ thanks. This was really comprehensive.. I appreciate.

kingschild123: There are several possible causes for this
problem.
1. Low Fuel
Fuel pumps work by pressurizing the fuel
and sending it to the engine. A low fuel
level can cause the engine to work much
harder to build the necessary pressure to
pump the fuel. To analyze the problem,
start the car when the fuel is low (below
one-fourth tank) and listen for the sound.
If the whine is audible, fill the tank
immediately. When you start the vehicle
again, the whine should be reduced or
absent. If not, there may be another
problem.
2. Damaged Pump
The whining noise may be caused by a
damaged fuel pump. The fuel pump may
be punctured or dented, reducing its
efficiency. To resolve this issue, the fuel
tank must be accessed and repaired or
removed. The location of the fuel tank
depends on the construction of the
vehicle. In a vehicle equipped with a
carburetor, the fuel pump is often located
outside of the fuel tank. With a vehicle
that has a fuel injector, the fuel pump is
located inside of the tank. It is best to get
a mechanic to address this problem.
3. Impurities in Gas Tank and Engine
If the fuel pump is blocked by engine
gunk, dirt, impurities in the gasoline or
anything else, it will respond with a
whine or some other very noticeable
noise. Debris in the fuel tank can be
sucked into the pump most easily when
the tank is low. This debris gets caught in
the pump and reduces the pressure. This
problem must be fixed by removing the
blockage which should be performed by
a mechanic. Using fuel additives that
clean the engine and keeping the fuel
tank filled may also be a preventative
measure.
4. Other Damaged Parts
A whining fuel pump may also be a sign
that other parts of the car are damaged. If
a hose that transfers fuel to the engine or
carburetor is damaged, it will release air
into the fuel system and reduce the
pumping pressure, resulting in the noise.
If a connection is loose between the fuel
pump and any other part, the same result
may occur. The vehicle should be
examined by a professional who can
pinpoint the damage and make repairs.

was finally able to fix it. The fuel pump was faulty. I had to get a really good one. I'm so pissed off right now because money was wasted on the other one and i did not get it back. Thanks again..