A fuel pressure regulator is an automotive part that is designed to keep the fuel pressure in the fuel delivery system constant and within limits. Excess pressure is bled back to the fuel tank in a bypass hose. Listed below you will find some steps to diagnose fuel pressure regulator related problems in your car’s engine.
Step 1: Note Symptoms
Certain symptoms will point at certain problems. For example, if your car hesitates or stalls, the regulator might be defective and closing down fuel flow intermittently. If, in conjunction with stalling, you smell a strong odor of unburned gas, the fuel pressure regulator is most likely not dropping the pressure going into the fuel rail sufficiently. This can be due to a defect, or a pump pressure is too high. Using an adjustable fuel pressure regulator can sometimes fix this problem.
Step 2: Test Pressures
In order to determine whether you need to fix or replace your fuel pressure regulator, you will need to test both the output pressure of the fuel pump and the output pressure of the fuel pressure regulator. You can rent or borrow a fuel system pressure tester at many of your larger retail parts chain stores.
Step 3: Scan for Codes
Another test you can run is to scan your car’s computer for error codes. When sensors in your car detect problems, they note this by sending a signal to your car’s computer. Some of the larger retail chain parts stores will let you borrow or rent a code scanning tool which will ‘pull the codes’ from the computer memory, interpret those codes and display the faults in plain English on their screen.
The above three steps can be taken if you suspect you’re experiencing problems with your fuel pressure regulator to verify the problem is or isn’t with the regulator.