X-man

I don’t know if this will help but I received a letter in the mail from GM years ago, it was in ref. to vehicles equipped with V8 engines may have condition where the throttle position sensor may cause the engine to run rough and cause the malfunction indicator lamp/or engine reduced power message to illuminate. GM would replace the throttle body if these symptoms occurred. This was only good for a limited time and mileage so it has expired by now. It may be worth checking this out.

I don’t know if this will help, but I have a 2008 Sierra that has the OEM nav unit. It did not come with Bluetooth. I swapped the VCIM which is under the radio for a 2009 and later unit that came with Bluetooth. To pair a phone using Bluetooth, the commands are <onstar> (Wait for response onstar ready)<Bluetooth >(response Bluetooth ready)<pair>