Here's a breakdown:
* How the System Works: Dual-zone climate control uses separate actuators for the driver's and passenger's sides. These actuators are small electric motors that control blend doors. These doors regulate the mix of hot and cold air going to each vent. If the actuator fails, or the linkage connecting it to the blend door is broken, it won't be able to properly direct the cold air to the driver's side.
* The Problem: A faulty driver's side blend door actuator is stuck in a position that primarily allows hot air to flow to the driver's side vents, while the passenger side actuator functions correctly.
* Repair Options:
1. Check the Actuator (Most Likely Culprit):
* Location: The actuator is usually located within the dashboard, often behind the glove box or near the HVAC blower motor. You'll likely need to consult a repair manual or online resources specific to your 1998 Oldsmobile Intrigue to pinpoint its location. Access may require partial dashboard disassembly.
* Testing: With the ignition on, but the engine off, listen for the actuator motor attempting to move when you adjust the temperature controls for the driver's side. If you hear no movement or a grinding sound, the actuator is likely faulty. You might even be able to visually inspect the actuator linkage to see if it's disconnected or broken.
* Replacement: If the actuator is faulty, it needs to be replaced. You can purchase a replacement actuator from an auto parts store (likely specifying "blend door actuator" and your vehicle's year, make, and model). Replacing it will require some mechanical aptitude and possibly specialized tools depending on access.
2. Check the Blend Door (Less Likely, More Involved): If the actuator seems to be working, the problem might be with the blend door itself. This is much more difficult to repair because it typically involves more disassembly and could mean replacing the entire HVAC housing. A broken blend door is usually caused by a malfunctioning or worn actuator, though.
3. Vacuum Lines (Less Likely): Some older dual-zone systems use vacuum lines to help control the blend doors. While less common in 1998, a leak in a vacuum line could affect the system's operation. Check for any obvious damage or disconnections.
4. Wiring (Least Likely): Faulty wiring to the actuator is possible, but less common than a failed actuator itself. Check for broken or loose wires connected to the actuator.
Important Considerations:
* Repair Manual: A repair manual specific to your 1998 Oldsmobile Intrigue is highly recommended. It will provide diagrams, instructions, and torque specifications to help you with the repair.
* Difficulty: Accessing and replacing the blend door actuator often requires significant disassembly of the dashboard. This is a moderately challenging job for someone without experience.
* Professional Help: If you're not comfortable working on your vehicle's dashboard, it's best to take it to a qualified mechanic.
By systematically checking these components, you should be able to pinpoint the cause of the problem and effect the necessary repair. Remember to always disconnect the battery's negative terminal before working on any electrical components in your vehicle.
