does the 2 pops happen when starting only if the climate controls would run the AC, or all the time? The AC will run when either the AC button is pushed or if the airflow is set to full or half defrost. When the AC engages, the magnetic AC compressor clutch can make a loud clack sound, usually one when it engages, quieter when it lets go
A grinding noise might be caused by one of the blet driven things on the engine. A relatively easy way to test that is when the engine is cold, remove the serpentine belt, start the car and see if the grinding noise is still there. Don't run the car for very long without the belt, but a quick test on a cold engine should be ok. On VIbes, a common belt driven noise failure item is the belt tensioner. If you think its the belt tensioner and go to replace it, be sure to first read
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