Check for any leaks in the vacuum lines or hoses that connect various components under the dash, such as the climate control system or the brake booster. A vacuum leak can create a whistling sound as air is sucked in.
2. Faulty Blower Motor:
The blower motor, which is responsible for circulating air inside the vehicle, can sometimes produce a whistling noise if it is damaged or obstructed. Check the blower motor and its housing for any obstructions or signs of wear.
3. Faulty Climate Control Actuator:
The climate control system uses actuators to control the flow of air and temperature. A faulty actuator can create a whistling noise as it tries to adjust the airflow.
4. Faulty Air Intake System:
If the air intake system, which brings fresh air into the cabin, has any leaks or obstructions, it can generate a whistling sound as air is drawn in.
5. Faulty HVAC Expansion Valve:
The expansion valve in the HVAC system, which regulates the flow of refrigerant, can produce a whistling noise if it is malfunctioning
6. Belt Tension:
Worn or loose belts driving components such as the alternator, power steering pump, or air conditioner compressor can also cause a whistling noise.
7. Failing A/C Compressor:
A failing air conditioner compressor or its associated components can produce a hissing or whistling noise.
8. Malfunctioning Fuel Injector:
A faulty fuel injector can create a whistling sound due to excessive fuel pressure or injector failure.
9. Exhaust Leak:
In rare cases, an exhaust leak near the firewall can cause a whistling sound that may be perceived as coming from under the dash.
Always consult with a trusted mechanic or automotive technician to diagnose and fix the exact cause of the whistling noise under the dash of your Dodge Durango.
