Originally Posted by Joshboody
Looks like both trims/AFR were logged and matching well. This seems to be a fuel pump issue. I don't remember the logging options in procede for fuel pressure, but you can use BT tool to see if you are short of target.
I believe HPFP would be more likely to throw a code... LPFP can easily be short of target without throwing a code. So if you wanted to "try" something, LPFP would be my guess.
He can log fuel pressure to confirm. If voltage is between 4.0 and 4.3 its operating normally.
Like he said he did not have any issues with the JB4. this is tune related.