J Wrote:

On the  4.6  engine check the PCV valve line tubes and hoses where they
go into the back of the intake.
They get soft and mushy and will suck air and give a lean code.
You will have to look real close and sometimes take them off to see the
problem.
I think the lines splits out on a T and goes to both sides or something
like that. :lol2:
Ford has a pcv line and PCV all in one  to repair the problem.
Check with your ford parts dealer.

On the egr code open egr vale and see if it makes the engine pull down
or run different.
If not remove the back part of intake and clean passages first.
They are bad about stopping up back there.
Good luck and let us know how it goes.
MT

It has been my experience that you have a couple of things
to do first.  The EGR code is likely the result of plugged
EGR ports in the intake manifold.  You must remove the
throttle bod and adapter from the intake manifold to clean
the slots in the gasket surface that serve as the EGR ports.
You will ned a new TB gasket unless you are lucky.

While you are there, take the opportunity to remove the IAC
from the TB and soak the valve end in good TB cleaner while
you continue with other things to help loosen the crud in
there.  Do not soak the solenoid end in solvent.  Finish by
giving it a good spray.  This may help extend it's useful
life.

The lean codes are likely a vacuum leak.  The PCV circuit is
frequently the cause of this because the hoses deteriorate
and crack.  The"Y" near the throttle body is a bad one.
They also plug easily causing the PCV system to become
useless and oil leaks start.  Replace all of the flexible
tubing in the circuit and make sure the firm parts are
completely open.

While you are cleaning, make sure you clean the MAF sensor
in the intake tube near the air cleaner box.  It tends to
become fouled making it sense less air than is actually
entering the engine.  The ECM controls fuel based on a bad
MAF reading - thus, the lean code set by the EGO sensors.
There are instruction for cleanig the MAF at several places
on the net.  Residue-free electronics cleaner from Home
Depot with a Q-tip used judiciously works well.  Don't
become too aggressive - use a bit more time.

Once you have completed all this, either have the ECM reset
or reset it by disconnecting the negative battery cable for
at least 10 minutes.  Start the engine without touching a
thing and left it idle to warm a few minutes.  Again,
without touching a thing, hold the brake and move the
selector among each of the position for several seconds
until it settles down bofore moving to the next.  Yoy should
then be ready to drive it a few miles for the ECM to start
relearning it's operating parameters.

You should then be good to go.

Good Luck, may you have a happy and prosperous new year

Lugnut