What this tool is used for
- Locating certain intake, vacuum, and EVAP leaks
- Checking sealed plumbing after visual inspection
- Observing leak location at an approved low test pressure
A tool produces useful evidence only when its rating, setup, test conditions, and reference limits are correct.
- 01ChooseLocating certain intake, vacuum, and EVAP leaks
- 02Set upConfirm the system, connection point, pressure limit, and approved smoke fluid / Isolate components that the procedure says not to pressurize
- 03MeasureInspect before connecting / Regulate to the exact approved pressure
- 04InterpretToo much pressure can damage seals or sensors
- 05RecordPreserve setup, conditions, result, and next test
Follow the sequence, stop when evidence changes the path, and verify the exact vehicle information before acting.
Before you use it
Confirm the system, connection point, pressure limit, and approved smoke fluid
Isolate components that the procedure says not to pressurize
Ventilate the area and inspect for fuel vapor or hot surfaces
A test-first working method
Inspect before connecting
Preserve the conditions and result so the measurement can support—or reject—the current diagnostic theory.
Regulate to the exact approved pressure
Preserve the conditions and result so the measurement can support—or reject—the current diagnostic theory.
Introduce smoke and observe without exceeding the limit
Preserve the conditions and result so the measurement can support—or reject—the current diagnostic theory.
Repair, retest, and confirm the original data pattern
Preserve the conditions and result so the measurement can support—or reject—the current diagnostic theory.
What the tool cannot prove by itself
- Too much pressure can damage seals or sensorsInterpret the result with circuit, system, operating-condition, and source context.
- Smoke visibility does not establish the effect on engine operationInterpret the result with circuit, system, operating-condition, and source context.
- Some valves and systems must be commanded or sealed for a valid testInterpret the result with circuit, system, operating-condition, and source context.
Safety boundary
Use only approved smoke and pressure
Never introduce an ignition source or unregulated shop air into a fuel-vapor system. Follow the equipment and vehicle instructions.