heater questions

[Guest TurboSedan]

do W-bodies have a heater control valve? if so....where is it? under the dash? or does coolant just run through the heater core all the time?

 

also, can someone describe where i can find the vacuum line for the HVAC? it connects to one of the fittings on top of the throttle body right? where does it go to from there? i can't seem to find it anywhere. this is pretty much the first time i've messed with the HVAC system on this car....i'm kinda lost.

[Supreme Cutlass]

I take it you need to know where it runs under the hood?

 

just trace it back from the vacuum check ball. There's plenty of threads about that vacuum line, what's the problem?

[Guest TurboSedan]

yeah, there is a vacuum line that went to the vacuum check ball under the battery that broke off. now i need to get another vacuum check ball from the j/y. so what you're saying is that this vacuum line is supposed to go from the vacuum check ball to the top of the throttle body? i was looking at it today and figured it went inside the car under the dash somewhere. i'll have to look again.

 

problem is my cruise control stopped working, and obviously my heater is stuck on the lower vents posistion. i'm not too worried about the cruise control....i still have to re-install that actually (hopefully it fits ok with the turbocharger right there). i just want to have windshield vent working again so the windows don't fog up.

 

today i installed a new GM heater core return pipe (that long one that runs along the firewall to top of water pump....cost $50 :? ) and i had to somewhat 'rig' the heater core supply pipe since my old pipe wouldn't work with the downpipe in the way...and the TGP-specific heater core supply pipe is discontinued. got all of that working....now i just need to get the vacuum part working the way it should.

 

thanks

[Supreme Cutlass]

just fix that broken line and you should be good to go.

[Guest TurboSedan]

ok....but the thing is is that i no longer have the HVAC line going to my TB. i totally forgot what i did with it :oops: the underhood diagram shows that the HVAC vacuum line goes off the top of the TB....but it doesn't show where it goes to.

 

i just looked under hood again. my CC is not installed, so bear with me there is one long vacuum line that used to go to the vacuum ball under the battery. this line comes from the vacuum ball and goes to a rubber 'T' near where the CC is/was. there is a line coming off the other side of that 'T' that is disconnected, and then just after that 'T' and before the check valve, there is another vacuum line coming off that is also disconnected. i assumed these two lines went the the cruise control? then there is one vacuum line on the other side of the check valve the runs into the wiring harness and looks like it goes inside the car and probably under the dash somewhere.

 

ok so:

 

- i know that the long vacuum line goes to the check ball under the battery. i just need to replace the check ball since the fitting broke off. this line goes to a 'T' near where the CC is/was...

 

- where does the other vacuum line that comes out of this 'T' go? cruise control? or top of TB?

 

- just after the 'T' and right before the check valve, there is another vacuum line...where does that go?