I completely understand now. You never said before that the past owner screwed up the lines. You need to check exactly what line goes to what before you go much further. You should be able to find a vacuum diagram for the car. I've seen them on eBay recently. I have a full wiring diagram coming for my '76 through the auction. It is still possible that the heater control valve is actually bad, but, without having the vacuum lines hooked up correctly, it is partially a crap shoot. I really don't want to do you a diservice by telling you to go and buy a new valve when it may be more in the problem with the vacuum lines. Try to correct that problem before you go any further. Understand, it's hard enough to diagnose a problem by "remote control", which is what I've been trying to do for you (and I do not mind in the least), but complicate the problem with hookups not being correct and it makes it extremely difficult to be accurate. I don't want to be the cause of you wasting money on something that isn't broken. I still think that it is part of your problem, but I cannot be sure until you fix the vacuum lines. I hope I haven't let you down. I'm still here to help. Don't forget, you can e-mail me direct and we can talk over the phone if you want. I would prefer not to put the phone number on here. Nothing personal, guys!!