Throttle acts up after I shift into neutral or reverse and back into drive

[JeffH]

Ever since I installed a L76 motor with a small cam (223/231 .610/.611 112LSA, removed VVT and DOD, 2600 stall, OBX headers, K&N CAI) into my 2007 GMC I've been having this issue. Basically what happens is my throttle will not work after I shift out of drive. Neutral and reverse do the same thing, and it only has to be out of drive for a second or two. I back up out of the garage, put it in drive and after a few seconds of slowly accelerating the throttle will not work. I can go full throttle and it won't break 2000rpm for a bit. If I let off completely for a second or two and slowly accelerate again it is fine.

From 20 to 25 seconds it did it, right after I backed up out of the garage pad.
Started again at 1:55 and at 2:02 is when it finally opened up. I stopped on the road, backed up and started accelerating slowly. When the throttle didn't work I went WOT and after slowly getting to 4000rpm it finally revved normal.
The third time at 3:10 it really didn't want to rev up. I had to feather the throttle quite a few times before it would actually start moving.

It is hard to see this happening in the log, you can notice the RPM needle flutter up and down just below 2000rpm, but the TPS doesn't even show me going WOT. Is this an issue in the tune or something else? I can idle all day in drive and its fine, only happens when shifting out of drive and then back in. I checked for codes after I got back and there was nothing shown.

[planethax]

post your tune as well

[JeffH]

Sorry, here is the tune file.