2006 6.0 commanding lean

[Jbeemer]

I have a 6.0 lq4 that is in a Jeep. A friend of mine did the engine swap and I turned off emissions, vats, and rear 02's. The engine is all stock except the air filter. It runs and drives great. I have a couple questions, it came up with a code for lean fuel trims. I did a scan (attached) and it has a lot of trims and at one point it was commanding 16.0 AFR. What would cause the lean commanded AFR? Do you see anything that would cause the high fuel trims. I am new to tuning and have only worked with some old black box ecm's. Any help would be greatly appreciated.

[5FDP]

If you changed the intake setup, you will likely need to do a maf tune.

Otherwise seeing +16.4 alot means you have a vacuum leak somewhere.

[mecanicman]

If you changed the intake setup, you will likely need to do a maf tune.

Otherwise seeing +16.4 alot means you have a vacuum leak somewhere.

Please explain to me how the PCM commanding 16:1 means he has a vacum leak.

OP, is the tune you posted the one in the vehicle right now?

[Jbeemer]

Please explain to me how the PCM commanding 16:1 means he has a vacum leak.

OP, is the tune you posted the one in the vehicle right now?

Yes that is the tune that is in currently.