A/C blowing out of Floor and Defrost Vents

[Dr76]

A friends 2000 Ranger (4-cyl, manual) a/c is only (or mostly?) blowing out of the top Defrost vent and Floor vents... very little from Dash vents. I have not yet looked at the vehicle, so just wanted a starting place... Is this possibly a vacuum issue? Are these controls still vacuum operated?

Thanks!

 

[Dr76]

OK, finally got a chance to take a look at this truck... Didn't find anything obvious under the hood leaking, so took out the a/c control panel and removed the vacuum harness from the vent selector switch. There was NO vacuum at the harness. I "T'd" into a vacuum line on the engine and applied vacuum to the harness, one line at a time. When I applied vacuum to the RED line, the dash vents worked as intended...

1) Shouldn't there be vacuum at the harness I removed?

2) If so, where is the source of the vacuum so I can see if there is a problem?

3) My HAYNES manual is pretty useless for this repair... where can I get a vacuum diagram for this truck ('00, 4-cyl, manual)?

Thanks!

 

[Psychopete]

You're on the right path. I am not fimilar with that particular setup, but have delt with a similar problem I had on a Grand Marquis. The car ran like crap only on defrost. What you describe is consistent with a foobared vacuum line to the vacuum controls. Is there any hint of where the vacuum source is coming through the firewall?

Most vacuum diagrams I've seen only show which functions are vacuum operated, but not where each line is and where it goes. But there could be something that exists.. You might have to sort it out, start and keep a diagram handy, until you narrow it down to the correct line. Then could be used for reference later.

I had a vacuum leak on my Tempo that I couldn't find to save my life. When I had to redo the rear brake lines, I had to rip out a bunch of stuff, which lead me to some vacuum lines that were cracked and dry rotted. Always keep a good eye out for anything that's "out of the ordinary."

Pete

 

[Wicked_Sludge]

theres a vacuum diagram attached the the core support under the hood of the truck. you probably leaned right on it while you were under there.

 

[Dr76]

"Pete" - Yes, vacuum leaks can be pretty tricky and do mysterious things for sure... I aslo have a '76 Stingray that has vacuum operated headlights and about 3 miles of vacuum lines connecting everything together! There must have been an easier way!

"Wicked" - I'll definitely ask him. I was hoping to find something more detailed (on my '93, it's pretty generic), but it JUST MIGHT be enough to get the info I need!!! Thanks for the "Do'h" moment!