Some more infromation.... sorry for the length.
I looked at your other treads and have the following comments:
1) I seem to recall seeing a TSR regarding the need to re-flash the chips inside newer explorers. You might want to investigate this. It could be a continuous source of problems, especially with a custom chip.
2) Regarding the service performed.
The Mass Air Sensor can be cleaned only. It can not be re-calibrated. It is a sealed unit that sends out a variable voltage signal. This signal is read by the EEC. the only "re-calibration" is to re-flash the EEC with different performance curves based on the MAS values. Could he have re-flashed the EEC yet again? (Truth is this sounds like Ford Service bullshit to me)
3) The TB can be cleaned and calibrated. Calibration is an unlikely requirement on a vehicle as new as yours. It ios only a screw adjustment to make sure the butterfly closes properly.
If the TB was particularly dirty I would consider inspecting the the idle air bypass valve (also called Idle speed control, ISC). It may also need cleaning. If it got very dirty it may be letting additonal, unmetered, air by which will make your engine run lean (not a good thing for the 5.0 engine).
4) The mechanics comment about "very dirty MAF and TB". If this is true it is bacause of the way the KKM filter is installed and/or maintained.
As mentioned in my other comments:
A) DON'T over oil this filter. Only a light coat of oil is acceptable. Over Oiling will cause excessivly dirty MAF, TB, ISC, and EGR components. As well as everything else downstram of the filter.
B) Also, DON'T hold the oil spray can too close to the filter when you apply the oil coat (I think the recomended 3" distance is way TOO close, I hold at about 9+ inches). If you are too close it will force the oil through the filter to the inside surface.
C) If you use color to guage the amount of spray, then the color is light red or pink, not RED

If you apply till it looks RED then you have way too much oil on the filter.
D) Make sure the oil has dried good before using. In humid climats like IL. give it twice as long or longer than KKM's recomended 20 minutes in dry Riverside CA. Wet oil will be sucked right into the plenum and contaminate the MAS, IAT and TB and other components.
As tempting as it may be DON'T use high pressure air to help dry the filter. If anything a blow dryer, on low setting, from the inside out might work.
2) You mentioned that there are no vacume leaks, but still make sure that there is a good seal where the filter attaches to the MAF. Also check the other connections along the intake tube to make sure they are tight and not leaking (Leaks in front of the TB will not show up in the vacume lines off the intake manifold). Any leakage between the MAF and the TB will seriously impact engine performance. The MAS sensor readings and the intake air temp. readings WILL be incorrect. The resultant air/fuel ratio determined in the EEC will be wrong.
3) I am very suspecious of this only because you have not shown how the KKM is installed. Did you remove the air box and is there a box around the KKM? Where is the cold air supply coming from? If there is not a box around the KKM, and a good fresh air supply (a real "cold air intake") then this could be the primary cause of the dirt and poor performance. I will try and explain....
If the filter is getting air from inside the engine compartment is it a) dirty, and b) HOT :fire:
The excessive dirt (contaminated air with heat, dirt and oil vapor) will add to the work the filter has to perform.
This heated air will affect the reading of both the MAS and the intake air temp. sensor (IAT). MOSTLY the intake air temperature sensor.
On pre explorer 5.0 engines the intake air temperature sensor is located in the #5 intake runner of the lower intake manifold. Just before air enters the #5 cylinder. The EEC unit has a set of temerature curves designed to account for the range of air temperature at this location to adjust Air/Fuel ratios.
Explorer 5.0 engines relocated this sensor. It is found on the air intake plenum (tube) just behind the MAF. Air temeratures at this location are VERY different, MUCH lower than on other 5.0 engines. The EEC is programmed for lower air temperatures. With an unprotected KKM air filter you are sucking in much warmer air over this temp. sensor (IAT). It is my belief that the air temp. curves embeded in the EEC won't properly account for the additional heat load in the intake air. It is exceeding the expected air temp. and running at the top, or above the air temperature curve in the EEC.
The intake air needs to be lowered to be in the expected air temperature ranges so that you get correct Air/Fuel ratio calculations from the EEC.
Air temperatures at this sensor and the MAS readings are critical to the EEC to calculate air/fuel ratio.
I suspect your solution is to get or build a real cold air intake. You could fabricate a box around the filter using cardboard, then coat it with fiberglass epoxy (you don't even need to use the fiberglass cloth). Use a single 3" diameter clthes dryer vent,or other such tubing to rout air from in front of the grill to the air filter.
Good luck.