Can a scan tool be used to check a fuel pump?
While this may sound complicated, it actually simplifies diagnostics. With a scan tool, it’s possible to verify if the modules controlling the fuel pump are receiving the correct data like oil pressure, crank position and key position.
How are pressure transducers used to diagnose fuel pump problems?
The pressure transducers can also be used to monitor system pressures to diagnose hard-start problems. So much of the diagnostic process for fuel pumps can be performed from the driver’s seat of the vehicle with a scan tool. This makes you a more productive technician and the diagnosis more accurate.
What do you need to know about fuel pump problems?
Most fuel pump-related problems could be solved with a pressure gauge and voltmeter. Today, the scan tool is the most important tool when diagnosing a fuel supply problem. On early vehicles, the fuel pump was energized when the key was turned on and a vacuum-operated diaphragm regulated fuel pressure.
Is there a problem with the fuel tank pressure sensor?
Sidebar: The diagnostic steps above cover the most common problems. However, in rare cases you could have a real fuel tank pressure problem. A malfunctioning vent valve or a defective pump that supplies the pressure to the tank for the test can also fail.
How are scan tools used to diagnose fuel pump?
Factory and enhanced scan tools can monitor pressure transducers on the high and low sides of the system. This information can be used to diagnose the health of the low-side and high-side pumps. These tools will have the PID parameters for these components as part of the Mode 6 data.
How to check the high pressure fuel pump?
You can check the high pressure system on turbocharged models using a MINI scan tool. Use the scan tool to view DME, then fuel pump / pressure. Look for the rail pressure set point (desired) and rail pressure actual. These two values should be pretty close. If it’s off by 10 bar, I would suspect a faulty high pressure fuel pump.
Sidebar: The diagnostic steps above cover the most common problems. However, in rare cases you could have a real fuel tank pressure problem. A malfunctioning vent valve or a defective pump that supplies the pressure to the tank for the test can also fail.
How can I tell if my fuel pump is faulty?
These signals are also displayed on a scan tool, and some scan tools allow you to issue pump speed commands with the tool. If pressure does not increase when the duty cycle is commanded high, either through a scan tool or at wide-open-throttle on a test drive, this could indicate a faulty pump.