Breather Line And Suction Line Inspection

Breather Line and Suction Line Inspection

Special Tools Required
- Fuel pressure gauge attachment set 07AAJ-S6MA150
- Vacuum pump/gauge, 0 - 30 in.Hg, Snap-on YA4000A or equivalent, commercially available

1. Remove the access panel from the floor.




2. Disconnect the suction line (A) from the fuel pump, and connect a vacuum pump/gauge, 0 - 30 in.Hg (B) to the hose as shown.
3. Start the engine, and check the vacuum.
- If there is vacuum, go to step 4.
- If there is no vacuum, replace the fuel filter.

4. Turn the ignition switch OFF.




5. Connect a vacuum pump/gauge, 0 - 30 in.Hg (A) to the suction line (B), and apply vacuum to the line.
- If the line holds vacuum, check for blockage in the suction line. If there is blockage, replace the line.
- If the line does not hold vacuum, go to step 6.




6. Disconnect the breather line (A) from the filler side of the suction line (B), then plug the suction line with a rubber cap (C).




7. Connect a vacuum pump/gauge, 0 - 30 in.Hg (A) to the suction line (B), and apply vacuum to the line.
- If the line holds vacuum, check for blockage in the suction line and the fuel tank vapor liquid separation valve on the breather line. If there is blockage, replace the fuel tank. If the breather line is OK, replace the suction line.
- If the line does not hold vacuum, go to step 8.




8. Connect a vacuum pump/gauge, 0 - 30 in.Hg (A) to the filler side of the breather line (B), and apply vacuum to the line.
- If the line holds vacuum, check for blockage between the suction line and the filler neck on the breather pipe, and replace the part that is causing the blockage.
- If the line does not hold vacuum, go to step 9.

9. Remove the rubber cap from the suction line, and reconnect the breather pipe to the suction line.




10. Connect a vacuum pump/gauge, 0 - 30 in.Hg (A) to the suction line (B), and apply pressure to the line.
- If the line holds pressure, the breather line and the suction line are OK.
- If the line does not hold pressure, check for a vacuum leak in the suction line, and replace the suction line if necessary.