I can see some residue around my coolant tank. So at some point I guess some has vented out the lid. I've also turned the bleeder screw on top of the tank a few times and let some air out. But not 100% sure what I'm doing when it comes to all of this...

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Current garage:
2006 X5 4.8is
2007 Lexus GS350
2011 Cadillac CTS-V Coupe