You can use carb cleaner to trace vacuum leaks also. Engine will rev when you hit the source of the leak. Are you sure the MAF sensor is plugged in? Had an engine act similar with the MAF unplugged.
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2012 GT Brembo M6, BBK CAI, Dynomax axleback, Bama tuned, UPR UCA & mount, Hotchkis LCA/panhard bar/adjustable swaybars, Whiteline relocation brackets, Barton shifter & bracket, Eibach ProKit Springs.