I just purchased 2005 F150 5.4 V8 and previous owner's mechanic had no regards to customer's vehicle and broke and mis-routed clips holding wires and vacuum lines.

I have fixed it as much as I can figure out from the pictures I found on-line, but I still cannot quiet figure out how this vacuum line is supposed to be routed.





It is the line between red line I drew.

Currently I have it tucked under PCM, but just doesn't look right for it to be just laying there without any mounting clips.

Before I went this far, it was just laying on top of the engine (top of the intake manifold to be more exact).


Can some one post a picture showing the correct route?

 

Mine just goes over top the PCM where yours turns down. It's not clipped anywhere, but seems to follow the wire bundle in front of the PCM(the one that is by the trans dipstick and goes to the yellow plug) then down. I think its zip tied or taped to it above the PCM Look at your picture and you can see the tape torn a little on the bundle right above the PCM I'll try and get a picture.

 

I tried routing the line above PCM, but hose seems too long if I do that. May be the rubber hose is clipped in wrong place to began with?

The tape on the bundle above PCM has no evidence of anything else attached other than ivory colored plastic clip.

 

Ok, see the big piece of wire loom, that goes around the line and wire bundle. Ignore the two red wires, those go to my amps.

 

Is that big wire loom original or was it added later? Looks newer than others.

Now I see what I am missing. I am missing that black plastic ring clip. I will substitute that with a zip tie.

Thanks for the picture.

 

Yes I added that, but the line is taped to the wire bundle there. Black plastic ring clip? If you mean the one below the ivory colored plastic clip, that is the check valve and is not attached to anything.

 

Mistaken that for a clip.
Does below picture look about right?

 

Looks good.

 

FWIW my line runs under PCM similar to OP's in first picture then to vacuum reservoir. It may be a "some years one way, some years another" or "some trucks one way, some trucks another" or could be that mine is routed "wrong" as well due to repairs prior to my ownership.

It's a vacuum line and it's not on a classic Bugatti show car going to Pebble Beach Concours d'Elegance, who cares where it sits as long as it's functioning correctly.

Side note: you might also want to do some due diligence and upgrade to the new style for the 4WD solenoid (with the water shield over it).

 

This is probably the only place I've actually seen that line connected and after my motor swap my mechanic has no clue where it goes. I know I'm never going to him again.

 

Does this help you?

 

Thank you tbear I knew it ran in that general direction but I don't have anything to connect it to on the other side. I've got a perpetual Bank 2 lean code since the I got the truck back and I suggest this to be the culprit even though I have it plugged atm

 

I think maybe goes to IWE solinoid? Has a check valve.

 

My iwe solenoid is being fed from the vacuum behind my throttle body at the moment. This mechanic caused more problems than I had when the motor was blown😩

 

Well, I went out to look closer. It goes into a junction behind the battery that looks like it ties into the lines from the IWE solinoid (two) and then a line goes into the fender out of sight behind the battery. Here is a diagram I found, might help. Likely that vacuum box is inside the upper fender behind the battery tray. The vacuum box stores vacuum so the IWEs will stay unlocked when engine vacuum drops due to hard pulls, etc.


In looking, I see that I let mine too become trapped below the PCM, had to be when I removed it to change spark plugs. It'll be OK.