2011 LTZ 5.3 Acceleration Problem

[derslayr992]

2011 Suburban LTZ 5.3L 2wd flex fuel 202,000

I recently purchased this beautiful machine but the only concern I have is that it seems to fall flat on its face when trying to accelerate from a dead stop, almost as if it is suffocated, until I reach 2500 rpm and then it takes off like a rocket. There are no CEL or fault codes being thrown and there isn't any other issues that I can associate with this one problem.
So far I have checked the air filter, spark plugs and wires, and have driven with the cylinder management disabled, still runs the same. I have a decent scanner and was able to pull the live stream data, but without any codes being thrown, I am not certain where to begin looking. The only thing that sticks out during my last scan was the Long Term Fuel Trims with bank 1 showing -10 while at idol.
If anyone could help with the deciphering of the data being shown in the live stream report, it would be appreciated!Live Data Scan

 

[zora]

2011 Suburban LTZ 5.3L 2wd flex fuel 202,000

I recently purchased this beautiful machine but the only concern I have is that it seems to fall flat on its face when trying to accelerate from a dead stop, almost as if it is suffocated, until I reach 2500 rpm and then it takes off like a rocket. There are no CEL or fault codes being thrown and there isn't any other issues that I can associate with this one problem.
So far I have checked the air filter, spark plugs and wires, and have driven with the cylinder management disabled, still runs the same. I have a decent scanner and was able to pull the live stream data, but without any codes being thrown, I am not certain where to begin looking. The only thing that sticks out during my last scan was the Long Term Fuel Trims with bank 1 showing -10 while at idol.
If anyone could help with the deciphering of the data being shown in the live stream report, it would be appreciated!Live Data Scan

Have you done a fuel pressure test both while running and after shutoff to check for leaking injectors?

 

[derslayr992]

I have. With the engine at idle the avg. is between 43 - 45 psi. With the engine off and the key on, 49 psi. I have scoured the Internet and can't find a solid answer as to if these numbers are within spec. Thanks for the reply.

 

[zora]

I have. With the engine at idle the avg. is between 43 - 45 psi. With the engine off and the key on, 49 psi. I have scoured the Internet and can't find a solid answer as to if these numbers are within spec. Thanks for the reply.

How long did it hold 49?

 

[derslayr992]

How long did it hold 49?

Roughly 13 mins.