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 tank unit, 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. Attach the fuel pressure gauge set. 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). Attach the fuel pressure gauge set, then plug the suction line (B) with a rubber cap (C).






7. Attach the fuel pressure gauge set. 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 recirculation tube. If there is blockage, replace the fuel tank. If the fuel tank vapor recirculation tube 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 air pressure to the line.

- If the air pressure holds, 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 air pressure does not hold, go to step 9.






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

10. Attach the fuel pressure gauge set. Connect a vacuum pump/gauge, 0 - 30 in.Hg (A) to the suction line (B), and apply pressure to the line.

- If the air pressure holds, the breather line and the suction line are OK.
- If the air pressure does not hold, check for a vacuum leak in the suction line, and replace the suction line if necessary.