Trouble code P1174

[solimx5]

HI to everybody, I am new to board and glad to find such group for X5's.
I am mostly fixing my cars myself including wife 2000 X5 4.4, but lately I do have problem with trouble code P1174. First I get it I find 2 rear house for oil separator was almost totally disolved and both valve cover gasket was leaking. I fix all of it, valve cover gasket was little PIA on driver site, but was done. And I thought this fix the problem, clear the code, but 2 days later code is back. My scanner say code P1174 Manufacture Control 1 Fuel Air Metering. Any idea what could be wrong or anybody have same problem with this code. I am thinking maybe air flow meter ( MAF sensor)
is a bad, but don;t want to spend $250 just to try. Any help will be appreciated.
milos

[The Cleaner]

Check the air boots for cracks (after the MAF). Check Vacuum pressure and Clean you MAF and see if it goes away. if the Vacuum is good and the code returns it's likely your MAF. Cam sensors are also possible but usually it's the MAF.