2001 Ford explorer lean codes

2001 Ford explorer p0171&174 codes.I replaced intake gaskets(orings) pcv valve and egr.fuel pressure hovers around 40 psi, kind of low I think.when I accelerate ltft goes from +24 to +14 but the stft spikes from + 12 to over 20. When I smoke test it it has a small leak underneath egr.What would trims look like with a small vacuum leak and low fuel pressure? I just need to get this pass inspection ! It has no drivability issues or maybe I just got used to them. Tia!

Watch the pre cat O2 sensors at 70% engine load.
If the stay high .8v then fuel pressure probably good.

Before I changed the intake Gaskets orings both ltft and short terms both went positive as expected with a vacuum leak. Now they go opposite directions when acceleration. 4.0 liter ohv 180k Vin E

If both banks are effected the same then monitor the MAF sensor.
Should be around 4 grams per sec at idle and increase up to maybe 100g/s at 70% load.

Both pre cat O2s read .8v at 70% load?

O2 sensors oscillating between .2 to 8 .Maf was changed out same readings as old one. Is 40 psi ok for fuel pump ? Doesn't back off at throttle any and holds pressure when shut down.

To expand on cj1's advice:

To determine if you have a fuel delivery problem, or not, watch your Oxygen sensors while at WOT. Under normal idle and cruising conditions, the Oxygen sensors should oscillate between .2 and .8, as you indicated they are. But, at wide-open-throttle, ALL oxygen sensors should go FULL RICH...flat-lined above .8 volts. By power braking, or wrapping out 1st or 2nd gear on a test drive, watch the oxygen sensors while at WOT. If they to not peg FULL RICH the WHOLE time, you have a fuel pressure/delivery problem.

Butchfuch wrote: Is 40 psi ok for fuel pump ?