Changing the faulty fuel pump in an engined bay that is pretty tight, in fact, requires precision, patience, and the right tools. Industry reports say about 15% of all car owners have a problem reaching their fuel pumps due to space constraints in modern engine compartments. In cars such as BMW 3 Series and Chevrolet Cruze, the engine bay is small, hence reaching some components such as a fuel pump may not be possible without dissembling some parts. The first step in such cases involves relieving the pressure in the fuel system, which can be achieved by removing the fuse for the fuel pump and then cranking the engine until it stalls. This will not allow fuel to spill during the process of disconnecting the lines.
Once relieved of pressure, disconnect the negative terminal of the battery for safety against possible electrical hazard. It’s also very crucial to use the appropriate fuel pump removal tool for your car model; using inappropriate tools can further damage other parts. For example, the common Honda Accord has a tight-fitting and mounting configuration that requires a special tool to remove the pump assembly. Sometimes the fuel pump itself is located inside the fuel tank, usually accessed by removing the rear seat or trunk panel, depending on the vehicle. This may be the more challenging task at times considering space, but it is imperative for safe and effective removal.
Identify the fuel pump; then disconnect the fuel lines and electrical connectors. Be sensitive to fuel spillage; 20% of fuel pump failures come from fuel lines that have been damaged or not properly connected in some cases, which can get worse in replacement. Once safely disconnected, remove the securing bolts and lift the pump assembly out of the tank. It is common in tight engine bays to be able to use a pair of angled pliers to free stuck fasteners or clips that may not be easily accessible.
This makes installation of the new pump in such a tightly confined area quite challenging. It’s great to make sure that the new fuel pump has the same specification as the old one, be it in voltage or flow rate; a mismatch may cause serious fuel delivery problems, reducing the engine’s efficiency or even causing damage to the new pump. According to a report provided by Car and Driver, incorrect installation of fuel pumps can result in a loss of up to 30% in fuel delivery, thus causing performance issues. Once the pump is installed, reconnect the fuel lines and electrical connections, making sure everything is tightened and secure.
The final step in testing the new pump is to reconnect the battery, replace the fuse, and turn the ignition to the “on” position. It should engage the pump, and a slight buzzing sound should be heard to indicate that it is working. If the pump does not turn on, recheck your electrical connections and fuel lines to make sure they fit properly. If necessary, a fuel pressure gauge can be used to check that correct pressure is being generated by the new pump.
Depending on the model and labor cost, the total cost to replace a faulty fuel pump in an extremely tight engine bay costs in the range of $400-$800. This is an important process that keeps the engine performance in place; a failing fuel pump can lead to stalling, misfires, or poor acceleration. For more information about fuel pump replacement and troubleshooting, check Fuel Pump.