I have an '01 2.3 5-speed that I just put a new engine in (same engine - 2.3). My father helped me in the swap from one truck to another and he was helpful enough to remove the vacuum lines from both trucks. He is now out of town and I've been instructed to button up the truck. I have most of the hoses connected except for one of the two hoses that goes to the reservoir. I traced one back to the air box but cannot find anything else to plug into it.. Help??

There is a vacuum diagram on the radiator support.

SFDROIDBIONICUT2

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2004 Ext Cab, 4WD, 4.0, Auto, 154k. (4.0 engine is out of a 2009 Ranger w/96k) ( as of 7/1/2017)

2004 Ranger, Ext Cab, 2WD, 3.0, 5 speed , 4WABS, crank windows, no cruise, Edge 116k.(6/5,2014) (SOLD).
1999 Ford Ranger, Reg Cab, 2.5, 5 speed, 2WD, no AC, 150k (SOLD).

I've looked at that and that controls the emissions systems and such. Not HVAC. I've currently got the defrost lock problem.

I dont understand. What is an air box? where the air filter is?

One line from the reservoir should go to the HVAC controls and the other to a vacuum source. On my truck it goes to the intake manifold.

SFDROIDBIONICUT2

__________________
2004 Ext Cab, 4WD, 4.0, Auto, 154k. (4.0 engine is out of a 2009 Ranger w/96k) ( as of 7/1/2017)

2004 Ranger, Ext Cab, 2WD, 3.0, 5 speed , 4WABS, crank windows, no cruise, Edge 116k.(6/5,2014) (SOLD).
1999 Ford Ranger, Reg Cab, 2.5, 5 speed, 2WD, no AC, 150k (SOLD).