Windnoise Diagnosis

Windnoise Condition


The first step of the repair process in correcting windnoise is to identify the cause(s) of the noise. A determination must be made as to whether the cause of the noise is air escaping from the vehicle or outside air turbulence.


To assist in diagnosing the cause of a windnoise concern, answers to the following questions should be obtained from the customer:


1. What specific noise is objectionable?

a. Whistle

b. Flutter

c. Rush of air

2. At what speed does the noise occur?

3. Does the noise appear to be:

a. Air leaving the body? (internal windnoise)

b. Air passing over the body's exterior surface? (external windnoise)

4. In what general area does the noise appear to originate?

a. Front of the vehicle

b. Side of the vehicle

5. Is the heater/AC blower motor ON or OFF?


ANALYZING WINDNOISE

When analyzing windnoise, it is important to understand the forces that act upon the vehicle that can create this condition. As air strikes and bends around the front of a vehicle in motion, it causes a low-pressure area to develop around the front pillars and side window locations of the body. At the same time, air flow that is filtered through the vehicle's vents and/or AC system will cause a high-pressure to build-up inside the passenger compartment. The faster the vehicle is traveling, the greater the pressure difference between the inside and outside of the vehicle becomes.






The high inside pressure and low outside pressure is separated only by the vehicle's exterior panels, glass, weatherstrips, and body seals. When an opening is created at a body seam or weak weatherstrip contact, the high inside pressure will move towards the low outside pressure and create an internal windnoise.


Wind rush or external windnoise is created by the air passing over and around misaligned body components such as mirrors, and door moldings.