No vacuum to close water vlv

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Ghostman
Posts: 11
Joined: Mon Mar 26, 2018 8:04 pm

No vacuum to close water vlv

Post by Ghostman » Mon Mar 26, 2018 8:53 pm

Air blows hot on my 69 Tbird even with temp lever on 65 degrees. Found no vacuum going to water valve to close it. Would appreciate any trouble shooting knowledge on this. It has automatic temperature control. Why couldn't I have the old fashion cable for closing door to heater core and temp control.

SABLT194
Posts: 31
Joined: Mon Nov 28, 2016 3:45 am

Re: No vacuum to close water vlv

Post by SABLT194 » Tue May 22, 2018 2:04 am

Sounds like your 69 has ATC like mine. Your HVAC system can have many issues that will cause it to blow hot, and while no vacuum control to the water valve isn't good, that's probably not the primary problem. Main problem on mine was dead vacuum control actuators. The worst one being what Ford called the servo valve actuator that controls the blend door as well as blower speeds. Also you'll need to make sure your AC system works as the ATC module blends cold AC air with warm heater core air to achieve a set temperature. So there's 4 actuators, 3 temperature sensors, the main brain box that houses some electronics as well as 12V vacuum solenoids, the ATC operator control panel, and quite a bit of vacuum tubing. All of which can cause your problem.

Don't ask me how I know ::?

There are specific sections of the service manual for trouble shooting this system. It's a must have IMHO if your going to fix the problem.

Regards,
Steve

Ghostman
Posts: 11
Joined: Mon Mar 26, 2018 8:04 pm

Re: No vacuum to close water vlv

Post by Ghostman » Tue Jun 12, 2018 1:37 am

Have not been on here for awhile. I appreciate your reply and info. Can you tell me where I can get a shop manual to trouble shoot this. I have one that pretty good for things like removal and installing components but it covers all kinds of other fords so it is definitely not specific to trouble shooting something like this. From what I have learned from looking at the system and following vacuum lines and looking at the ATC control box. Your are dead right there is many things that could be wrong. Appreciate any more info you can give me or where I can get a manual that shows step by step trouble shooting and vacuum sources.

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