How to Test Fuel Pressure On Your Car

Your car is running poorly or not at all, I will show you how to test your fuel pressure to determine if that is the source of the problem.

Things You'll Need

• Fuel Pressure Gauge
• Adapters for your vehicle

Instructions

1. 

   Locate the fuel pressure test port, you may have to refer to service information to locate this port or you may have to T into the fuel supply line.

2. Cycle the ignition key "on" and check your readings, write this number down. Start the car and run it, record your fuel pressure reading again. If your performance problem occurs when driving then you will need to take a road test to record the fuel pressure when driving. Tape the gauge to the windshield and have an assistant watch the gauge while you drive.

3. Compare your reading with specifications for your car, if it is low then I would start by replacing the fuel filter and retest. If there is no pressure then the pump may be at fault. Perform electrical tests on pump before replacing it.

4. Make sure everything is back together and no fuel leaks are present. Thanks.

Tips & Warnings

• An empty fuel tank will result in low fuel pressure, add a can of gas to the tank before you condemn the fuel pump. A defective sending unit can be show there is fuel in the tank when really there is none, but the pump might be ok.

• Gasoline is flammable and your car could burn up if it catches on fire, make sure you have no leaks and lines are routed away from hot surfaces when routed to the windshield. If you see a fuel leak turn off the engine immediately.

Resources

• Fuel Economy Fundamentals