I accidentally broke the vacuum line that goes to my heater control valve......but the heater still works?! So exactly what does the valve do? Can i take it out and just connect the heater hoses to clean up the engine bay and still have the heater work, or is the valve still doing its job? Thanx

 

The vacuum line comes from your heater controls. When your heater is turned to the "off" position, it closes the valve and stops coolant from flowing through your heater core.

I removed it on both of my cars. I've had no problems with either.

 

Cool. So if I take it off, then when i turn the controls to the "off" postition, instead of stopping the flow of coolant, it will always flow freely? Thanx

 

Yea but now your heater is on. Plus you will have a vacuum leak if you don't plug up that vacuum line that goes to the heater valve that you broke.

 

Yes, coolant will still flow through the heater core, but as long as your temperature slider works, the heater door box will be closed, so the amount of heat that gets into the car will be minimal. It's no different than driving around with the selector in "heat" mode but with the temp all the way down and the fan off.

As for the vacuum leak, uh, well, just plug it.

 

Ok. I finally got around to looking at it and figuring out how to bypass it....and well, i have a question. Which of the 3 hoses is removed and which two get connected?

 

On my IROC I just ran a new line from the throttle body directly to the heater core, and from the heater core directly back to the radiator.

My GTA has an oil cooler, so I did it somewhat different. I ran the output of the heater core to the oil cooler, then the other side of the oil cooler to the radiator.

 

Ok. So what would happen if I went from the radiator, to the heater core ( one of the hoses coming from the firewall) and then from the heater core ( the other line coming from the firewall) to the intake manifold? Sorry for dumb questions, but i dont want to cut up the heater hoses more than once. Thx.

 

That would work fine... some cars (Camaros esp.) were actually plumbed that way.