if you get the increase in rpms like that,it's a vac. leak.you need to find it.check your hoses on the cai and make sure there tight.if they can;t be any tighter,go from there.

 

I have an 07 Gt and have been running the C&L intake and use the Brenspeed tune with the SCT Xcal2. Since I have never had anything like this before, I have nothing to compare it to, but is there any way you could get the Xcal2 or is that what you have? Mine has all three tunes as yours does, but it just works perfectly all the time.

I have never had a fault code any time. I am not made of money, and could understand you not wantng to spend more your self. I bought mine on the strength of what I read in here, and everybody liked it. But you can see I am no expert. I hope you get it fixed soon in any case. Good luck!!