hi everyone. I know I'm a noob, and I should search the forum for this, and please know I did put in a valiant effort. Yesterday I serached the forum, and could not find a copy of the vacuum line routing for a 97-03 body style 4.6. All the threads i have seen indicate there should be a sticker under the hood. This sticker isn't on the truck i just bought.

I have found a couple threads where someone has posted a picture, but it was removed from the photo sharing site sometime in the past. Is there a FAQ section for this body style that has a copy of the vacuum line routing? I have 4 trouble codes, and before i start throwing parts at this thing, I'd like to check all the easy stuff first.

So here is what I have:

Codes:
P0401
P1131
P1132
P1151

Done:
* replaced fuel filter (it was original with 137k)
* installed correct gas cap (had one from a completely different vehicle)
* pulled the throttle body elbow off and cleaned the EGR ports and replaced both EGR and throttle body elbow gaskets
* cleaned the throttle body itself, along with the MAF sensor and EGR valve and verified the diafram is opening
* replaced DCFM

I have purchased a new upstream 02 sensor for the driver side (I think that is bank 1), but have not installed it yet. There is a vacuum line on the passenger side of the firewall that has been capped, but I have no idea where it goes, due to the lack of the under hood diagram missing.

In this picture, you can see the blue line cap on this box mounted to the firewall.


In this picture, it looks as though this box has been modified like something was cut off.


It has a set of lines running to the bottom of it. I don't have a vacuum guage, or access to one, but i have a really good feeling the shafty running is due to a vacuum leak. I have already done all the other repairs, and checked the wiring.

Thanks for any help anyone may be able to offer!