Nope no dis-assembly required, you did good on cleaning the MAF sensor.
Good to hear it seems to start & idle better, but the P0171 & P0174 codes are for a lean condition on boh cyl banks & suggest a vacuum leak somewhere,
I agree, the PCV & it's pumbing belong on your suspect list, as well as any vacuum lines to things like the vapor recovery system, brake booster, AC/Heater controls & intake manafold gaskets.
You might consider trying a rigging a propane "sniffer" tester, with an unlit propane torch & a length of tubing attached as a probe, & check around vacuum leak suspects, to see if idle speed increases as the engine gets a sniff at the vacuum leak. Prpoane won't hurt the O2 sensors, cat converter, or underhood rubber, plastic or composit parts that some sprays can.
If it seems to be leaking around the intake manafold, maybe try re-torquing the intake manafold fastners to spec.
The rubber hose from the air tube, running over to the valve cover is the fresh air intake hose for the PCV system.
Not sure of the OHC 4.0L PCV set up, so you need input from an OHC 4.0L owner!!!!
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