How many fuel pumps are in a car

This diesel fuel pump is also controlled electronically by various sensors, an electronic control unit, and an actuator. The actuator controls how much fuel is injected and its timing according to the signals it receives from the control unit.

In-line fuel injection pump. One of two mechanically controlled diesel fuel systems, the in-line fuel injection pump matches the engine cylinders in their number of fuel pressure mechanisms. This pump is primarily used for medium to large trucks and construction machinery.

A camshaft drives the fuel pressure and injection quantity control mechanisms within the pump body. Petrol is pumped along a pipe from the tank and mixed with air in the carburettor , from which the engine sucks in the mixture. In the fuel-injection system, used on some engines, the petrol and air are mixed in the inlet manifold. A fuel pump draws petrol out of the tank through a pipe to the carburettor. The pump may be mechanical worked by the engine - or it may be electric, in which case it is usually next to or even inside the fuel tank.

Inside the tank, a float works an electrical sender unit that transmits current to the fuel gauge, signalling how much petrol is in the tank. The tank has an air vent - usually a pipe or a small hole in the filler cap to allow air in as the tank empties. Some of the latest systems have a carbon filter , so that fuel fumes do not escape. A mechanical fuel pump is driven by the camshaft , or by a special shaft driven by the crankshaft.

As the shaft turns, a cam passes under a pivoted lever and forces it up at one end. The other end of the lever, which is linked loosely to a rubber diaphragm forming the floor of a chamber in the pump, goes down and pulls the diaphragm with it.

When the lever pulls the diaphragm down, it creates suction that draws fuel along the fuel pipe into the pump through a one-way valve. As the revolving cam turns further, so that it no longer presses on the lever, the lever is moved back by a return spring , relaxing its pull on the diaphragm.

The loosely linked lever does not push the diaphragm up, but there is a return spring that pushes against it. The diaphragm can move up only by expelling petrol from the chamber.

There are a few maintenance tips that you can follow to increase the longevity of your fuel pump:. The warning signs of a faulty fuel pump are pretty blunt compared to some other parts of the car that can leave you guessing. If your car is experiencing these symptoms, it may be due to a fuel pump issue:. But to get a little more specific, your fuel pump serves as the heart, pumping fuel away and into the parts of the car that need it to do their job. We know about the importance of regular maintenance and specialize in fuel system cleaning and repair.

Stop in any of our locations to talk with one of our professional mechanics or schedule an appointment online to get your vehicle serviced. Car Care Tips Tips to keep your car on the road. Maintenance September 13, Tweets by VATireandAuto.