air just blowing out vents not def or floor very little

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air just coming out of vents, ac or heat I can hear the blend door working digital control system I ran for codes all 8.s I'm thinking vacuum leak somewhere maybe is there any modules ?????? help

stewie33bb18f6 in Lynn MA

Apr 12, 2017

2 Replies

Popular Answer

pushrodon Apr 12, 2017

Electronic Temperature Automatic Control > ETAC module is suspect .. 'Defrost' is default mode. Remove ETAC and test the vacuum circuits manually .... It's pretty easy to do! Check out this video link: https://youtu.be/hAqE-oYnvlQ

stewie33bb18f6on Apr 12, 2017

Hi pushrod I found this video before while looking for some help, I did change the rubber o rings on the EATC module (from another video) also I ran the test you referred me to all 888. What else do you have? thanks

pushrodon Apr 12, 2017

Remove ETAC unit from dash .. Remove vacuum tubing 'bundle' from rear of unit .. Using a small piece of vacuum hose about 8" long with a connector at each end, probe the vacuum 'source' tube at the bundle and then insert other end into different tubes in the bundle until all 'air flow modes' have been tested and confirmed .. I use a Mityvac for testing but this method works well also.... (Engine running of course.) .. IF this test is done right, it will lead you right to the problem or make problem obvious via process of elimination! ..... You may need to visit parts store to get vacuum hose and plastic connectors... Good luck!

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casey40510on Apr 12, 2017

Hello, There are actuators that power mode doors in the HVAC box (behind/under the dashboard). You may, or may not, have a bad fuse, but that is not entirely likely. The most likely possibility is that the mode door actuators, the mode doors, or the control unit (the buttons on the dash) are faulty, and must be tested to determine which is the culprit. Ford has lots of problems with mode doors breaking, and mode door/blend door actuators failing.

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