xJimbos

From what you said about the clunking/grinding noise and then you said that the IWEs are not holding vacuum I can tell you need new IWE actuators. They are....somewhat easy to remove. The big pain is manipulating the steering knuckle so that you can get enough room to remove the IWE actuators from the half-shafts without damaging the CV joints. (Yes you can remove the halfshafts from the axle but I didn't have enough room when I did it) I had to pull the knuckle off of the upper control arms to get mine out, but I didn't have a lift or anything either, just jackstands. Not fun! Man were those things on tight.

The parts are relatively cheap though.
Like other have said, just cut that melted part off the vent hose. I would get some zip ties too and tie up those vacuum lines away from the engine.

BTW, I had a tiny bit of water in my 4x4 vacuum lines and did not know until it was really cold and snowy out and that little bit of water froze and locked in my 4x4.

60DRB

...If you still get no vacuum on your "sealed" check on the IWEs themselves, then yes the IWEs are shot. The item on the firewall is the solenoid. "Actuator" is a term most of us use interchangebly for the IWEs. The trouble shooting info by xjcamaro89 is what most people use and is good info.

As far as replacing the IWEs, you should be able to replace them without removeng the half-shafts. I did both of my IWEs by myself, and left them (the shafts) in/on. I did mine with only the tire changing jack, which I DON'T recomend.

Read/review;

http://www.f150online.com/forums/2004-2008-f-150/360269-iwes-removal-replacing.html

I think the required tools are listed there too, but I can list them for you if not...

88rxn/a

thank you so much for the info!
turned out one of the check valves was bad. the valve was on the bottom line right off of the solenoid located on the firewall. i tried driving around to listen but it is raining SO HARD i couldnt hear anything but tires humming and water/rain!
also, after getting a line that fit the IWE properly they both tested and held fine.

88rxn/a

FAIL.
the check valve i bought wouldn't hold a vacuum for anything!
back to square one.
gonna have to wait until tomorrow to buy another one.

Skitzo

so what ended up being the problem?

p.s sorry i rose this from the dead but its nice to have input fron his troubleshooting!

ArcanNascent

I just bought an '04 FX4 and had the grinding noise. I narrowed my sound down to the actuators causing the grinding (most cases due to the IWE solenoid, mine was replaced and still it was happening). I changed out the actuators on both sides (bit of a pain due to the space between the CV joint and the skid plate on the FX4 driverside), but I'm still getting the grinding sound intermittently on hills but goes away once I let my foot off the gas...

Wondering if you were able to figure your problem out and help steer me in the right direction as well...

LiftedsKRew

If you've changed your actuators, the likely culprit is your vacuum lines themselves or a check valve. Plug the end of the lines at your actuators and put a vacuum pump on the end by the solenoid. Go from there to see where its leaking.

Rick_F150

so is it normal to have a open end of the vaccum hose as a breather cause i been looking for a long this a few different time can seem to figure out where it goes too...
thanks

techrep

iTrader: (1)

You have a Vacuum line and a Vent line...the Vent line is open

VTX1800N1

https://www.f150forum.com/f72/how-diagnose-your-4x4-system-esof-186872/