I have a 2001 ford f150 4.2L 2wd. I'm looking for the vacuum diagram for the truck, mostly the vacuum line going to the heater control valve. My truck doesn't have a heater control valve under the hood. causing no heat in the winter. I replaced everything else in the coolant system. Instead of the control valve it has just a coupler in place. I don't know where the vacuum line is going to the heater control valve. I looked everywhere under the hood for the vacuum line.

 

If you look near the battery toward the firewall there is a vacuum line that goes into the firewall next to the starter solenoid. I think that is it, from the intake. T's off to behind the battery to a canister.

 

Ok, I've seen that vacuum line, wasn't sure what it's for. Have to see if that works.