How to Pressure Test a Gas Tank

by Alissa Jordan
itstillruns article image
pressure guage image by Jeff Davies from

Fuel problems can be difficult to diagnose without paying the host costs of a repair shop. Pressure testing is an excellent, inexpensive way to troubleshoot problems with gas tanks and fuel pump systems. By pressure testing, you can rule out certain conditions, such as a leak in the tank or a plugged outlet. This quick method demonstrates pressure testing while the tank is still inside the car, reducing labor costs.

Step 1

Locate the supply and return lines running out of the tank reservoir. Clamp the supply line tightly with a pair of needle nose vise grips. Clamp return line tightly with a pair needle nose vice grips.

Step 2

Find the overflow house next to the fill spout and clamp with the remaining pair of needle nose vise grips.

Step 3

Place a rubber grommet of correct size into fill spout, pushing hard to ensure a complete seal. Pump pressure tester up to 10 pounds per square inch (psi). Do not exceed 12 psi. Let it stand for five minutes.

Step 4

Check the pressure tester gauge for the psi readout. If the pressure has dropped from the original reading, there is a leak. If pressure has held, the tank is leak-free.

More Articles

article divider