The Road Test

WINDNOISE CATEGORIES

THE ROAD TEST

To analyze a reported windnoise condition, a test drive in the vehicle is necessary due to the many variables that could singularly or collectively be attributed to creating the objectionable windnoise condition.

NOTICE: OFTEN THERE IS ONE PRIMARY LEAK SOURCE AND ONE OR MORE SECONDARY LEAKS THAT CONTRIBUTE TO THE NOISE CONDITION. REPAIRING ONLY ONE OF THE CONTRIBUTING LEAK SOURCES MAY NOT COMPLETELY REPAIR THE TOTAL CONDITION, BUT ONLY REDUCE IT.

FOR SAFETY REASONS: An assistant should drive the vehicle while the technician checks for the location of the reported condition(s). In addition, the following items should be taken for utilization by the technician during the test drive to aid in pinpointing and marking area(s) of the leak:

1. Mechanics Stethoscope or Vacuum Hose.
2. Masking Tape (2" in width).
3. Strip Caulk.
4. China Marking Pencil.
5. Screwdriver.

A regular route for the road test should already have been chosen. The road test should include smooth and straight streets that run in all four directions, (North, South, East and West). It should be an area where there is little traffic or noise that would interfere with the test.

The vehicle should be driven at the speed in which the noise was noticed by the customer or until it is heard. Safe legal speeds should never be exceeded.

First determine if the noise is an objectionable windnoise as opposed to normal or standard sounds.

If noise can be heard with the door glass lowered and vehicle is being driven, it is EXTERNAL WINDNOISE.

Locating an EXTERNAL WINDNOISE condition can be accomplished by taping various moldings and gaps until the noise is eliminated to pinpoint the exact cause of the noise.

If noise cannot be heard with the windows lowered, this indicates a body seam is leaking or a sealing surface such as a glass to weatherstrip or door weatherstrip to door is poor. INTERNAL WINDNOISE is air leaving the body.

The first step in locating the source of INTERNAL WINDNOISE is to tape off the body lock pillar pressure relief valves. This will cause air pressure to build-up inside the vehicle and enhance the windnoise. Trace the suspected seal using the stethoscope or section of vacuum hose to locate the leak area.

FIGURE 6:

Temporarily repair the condition with masking tape (Figure 6). Adjust tape as required. Continue testing to determine if noise has been eliminated or other leak areas exist.

When all reported leak conditions have been located, return to shop and make permanent repairs utilizing proper alignment techniques and sealing materials as required.