Having problems with your 2001 Jeep Grand Cherokee ?
When the engine is shut off I can hear what i think is a door or something in the AC system behind the clove box open and close from time to time. Any ideas about what this might be?
You probably have a small leak in your HVAC system. It operates the doors using vacuum and defaults to defrost when there is no vacuum. The system stores vacuum so that the setting doesn't change when you shut off the engine. However, if there is a small leak the system may work fine but would leak into the default when you shut off the engine. This is not an issue, but if it gets worse the switch may stop working. Recommend you look for the small (usually black) vacuum line that goes from the engine intake manifold thru the firewall to your HVAC switch and see if it has a leak. You can also check under the dash to see if any of the various vacuum lines running the system are leaking or off their actuators.
Repair Help & Product Troubleshooting for 2001 Jeep Grand Cherokee
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