Conditions for Setting the DTC
WARNING: This page is about a different car, the 2018 Chevrolet Suburban 3500 HD. However, it is still accessible from the selected car via links, so may be relevant.
P0506
The actual idle speed is approximately 91 RPM lower than the desired idle speed.
P0507
The actual idle speed is approximately 182 RPM greater than the desired idle speed.