The fuel tank leak test is used to locate any fuel or fuel vapor escaping the fuel tank area. Fuel vapors escaping above the fuel level will be detected when the evaporative emissions (EVAP) leak diagnostic completes one test cycle.
• | Operate the vehicle under the condition of the customers concern. Under high temperature conditions fuel vapors may increase to the point of EVAP canister vapor saturation. Fuel vapors would then be released into the atmosphere. Once the engine is running and EVAP purge is enabled, all fuel vapor release would be eliminated. |
• | Movement of the EVAP pipes or fuel pipes may help find an intermittent condition. |
This step tests for location of fuel leakage in the fuel lines.
This step tests for fuel leaks below the fuel level in the fuel tank.
This step tests for a location of fuel vapors escaping above the fuel level in the fuel tank.
Step | Action | Yes | No |
---|---|---|---|
1 | Did you perform the Diagnostic System Check - Engine Controls? | Go to Step 2 | |
2 |
Caution: Gasoline or gasoline vapors are highly flammable. A fire could occur if an ignition source is present. Never drain or store gasoline or diesel fuel in an open container, due to the possibility of fire or explosion. Have a dry chemical (Class B) fire extinguisher nearby.
Did you find fuel leaking from the fuel tank? | Go to Step 7 | Go to Step 3 |
Did you locate a fuel leak from the fuel pipes? | Go to Step 8 | Go to Step 4 | |
Did you locate a fuel leak from the fuel tank? | Go to Step 7 | Go to Step 5 | |
Did you locate a leak source? | Go to Step 6 | Go to Diagnostic Aids | |
6 | Repair the system as necessary. Did you complete the repair? | System OK | -- |
7 | Replace the fuel tank. Did you complete the repair? | System OK | -- |
8 | Replace the leaking fuel pipe. Did you complete the replacement? | System OK | -- |