I put the Kooks headers on the truck with the catted Y pipe. Following that I had a custom tune written and it has been nothing but disappointment so far. It doesn't matter what the tuner does the P015B and P015D continue to plague me. The truck feels mushy like its always bogged down. I don't know what else to do besides try another tuner. I need help with this.

 

Yeah those codes come up as upstream o2s. I'm sure your AFRs are way off that's why it feels mushy. If you had a wideband you could see what's going on

 

You answered your own question. If your not happy go somewhere else.

I wasn't aware the 2012 ECU's were able to be tuned as of yet. My understanding was that GM locked them out.

 

My only issue is whether it is the tune. I didn't know if maybe it could be caused by a header leak, a leak where the y-pipe merges, etc. I have a 2012 Camaro with a custom tune from the same place and it runs perfect. I know these are hard questions to answer without more info, but I'm at a loss on this one.

 

take the truck back to the tuner and tell him what you are experiencing.....

 

It may be hit or miss on the 12's as to which ones and what can be touched. With the little '12 model GMC Canyon I have with the 5.3L, we were able to tune the ECM, but suprisingly not the TCM as of yet. You would almost think that since the 4-speed trans has been around for so long that even though the TCM changed it would take very long to get up to speed, yet it has still been about 8 months and we still can't tune it. The ECM was no issue what's-so-ever with EFI Live, but again at the time we couldn't do it with HP due to HP flashing the ECM & TCM together, whereas EFI Live flashes them seperately.

 

P015d just popped up on my 2012 with lt headers. Did you ever figure out what the fix was?

 

It sounds like you need to go somewhere else for tuning. All tuners are not created equal. Some just dont care, and want your money. Others will tweak anything you want until it is perfect. I learned this after numerous problems with my first tuner before I decided to cut my losses.

 

This thread is 1.5 years old

 

Oops. Ha ha. I didnt even look, just responded.