Engine Schematic

Local auto parts store or parts dept at the ford dealer will both have a schematic.

Have you looked under the hood? Mfgs have placed a diagram there for years.

Underhood label only covers a few components. Since it might be an emissions part, it might be covered by that label.

OP, if you'll post a pic of the part in question, might help us tell what it is.
Also, I have a Haynes manual which is far from the best. If you send me a Private Message with your email ID, I'll scan what I can find and email you a .PDF of it.

Had a similar situation last year, but in our case it was rats. There are vacuum lines that run as you describe that control the heater vents to switch from defrost to floor vents. You may want to check if yours still work.

End of the day tried to find a schematic, (did find some online, but could not read them) with little success. Called around found a shop that seemed to be pretty familiar with the issue. Couple hundred bucks later, good to go.

As a side note, which you probably are aware of, the MH is 2003, but the chassis is going to be 2002

Good luck with it

Thanks for all of the responses.
In this case fortunately I had a friend who has a different model but basically the same year/chassis.

The component in question was the Idle air control valve which I might be able to get away with just replacing the connector and not the whole valve. The valve is only $60 but a pain to replace due to where its located.
The there were 3 vacuum lines which manifold into 3 separate components. They all tie into a 3 way manifold that goes to the intake where the vacuum is created.
1) Controls the heater blending
2) Controls the Fuel regulator
3) Not sure what it controls but I know where to connect the vacuum line on the other end so it does matter at this point.

If you hear a "hooting" sound, like a distant ship's whistle, or a long low note on a saxophone, that's a failed IAC (Idle Air Compensation) Valve. Does it look like this
Does your last post combine two problems: A damaged Vacuum Hose AND a bad connector on the IAC? I ask because the IAC doesn't have a vacuum connection. Just Connector, Gasket, Two Capscrews.

j-d wrote:
If you hear a "hooting" sound, like a distant ship's whistle, or a long low note on a saxophone, that's a failed IAC (Idle Air Compensation) Valve. Does it look like this
Does your last post combine two problems: A damaged Vacuum Hose AND a bad connector on the IAC? I ask because the IAC doesn't have a vacuum connection. Just Connector, Gasket, Two Capscrews.

You are correct. There are several parts to of the damage these critters created.
They chewed through 3 vacuum lines and the electrical connector for the IAC. The also chewed the plastic part of the end of the IAC which is why I have contemplated replacing the whole IAC. The IAC does not have many things to remove but its in a tight area so we'll see if the electrical connector fixes it and go from there.