Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Energizing The Fuel Pump
All of the fuel system tests will require operation of the fuel pump to measure pressure, evaluate pressure decay, or perform the pressure at calibrated flow tests.
Although the fuel pump can be controlled with the ignition, this is fairly awkward for the following reasons:
- The pump is only energized for 2-3 seconds at Key On (and then a wait of 10 seconds is required after Key Off before the pump can be powered again).
- Some of the tests are run with the vehicle on the hoist with control of the pump under the car required.
- The pressure at flow tests require the pump to run for 10-20 seconds.
The Scan tool provides control of the fuel pump at the technician's finger-tips. The tool will run the pump for one minute after the On command. This timer will then shut the pump Off.
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Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.