I know there are others who have posted results on different intakes causing Lean conditions.
A little background I have a 05 v6 4.0, I have the TRD SC, JB Headers, magnaflow exhaust, 2.8 pulley, and the TRD intake. After a month the truck popped a p0171 Lean code and then right after a p0101 MAF problem. I thought hmmm what would cause that. I used my scan tool and this is what the fuel trim was saying
I had purchased the upgraded fuel pump from URD a few months ago and never installed. I decided to install the pump and see if that would fix the issue, well it didn't.
I had my K&N intake sitting around still so I figured I would swap and see what the fuel trims would say and this was the result.
The TRD increased the fuel trim by about double, I guess with the design of the intake being much larger in diameter than stock it increases the amount of air too much and the MAF is still reporting the normal amount of air that a stock intake would produce. The end result is too much air being mixed with the regular amount of fuel causing a LEAN condition.
I know there are users here that have the SC and TRD intake and have no problems, but in my case I did. So looks like I will be selling a brand new TRD Intake here soon
I bought a stock intake from a user here and it should be here today I am going to do the same thing and post the results later on.