My 03 expedition I just got is only blowing from the defrost vents. I checked a few forums and my actuator is good, no clicking etc, but I read about the vacuum lines. I have one coming from the firewall into a grommet with others (attaching pictures), but it doesn't look like everyone else's. there's also screw at the bottom. No noticable other hoses to connect. And they all are pretty much in tact. A little lost and could use some help.
03 XLT 4.6 only blowing out of defrost. Can't figure out hoses. PLEASE HELP
- Thread starter tuuzoo
- Start date
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Hamfisted
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Is it a 4WD Expy ?
That's a previous owner's hack job.
Do you see a vacuum supply line ( hard plastic tube... ) going into the firewall just below the PCM computer ? You should see the hot water valve vacuum control line paired up sharing the same firewall grommet.
But whatever you have there, you need a vacuum supply line going to the dash vent control solenoid up under the center dash panel to control the vent airflow.
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That's a previous owner's hack job.
Do you see a vacuum supply line ( hard plastic tube... ) going into the firewall just below the PCM computer ? You should see the hot water valve vacuum control line paired up sharing the same firewall grommet.
But whatever you have there, you need a vacuum supply line going to the dash vent control solenoid up under the center dash panel to control the vent airflow.
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It's a 2wd, and no I don't have that vaccum line under the PCM. Not really any gromets there. I also don't have a hot water valve either. I will look again here shortly. But there is no vaccum line under the PCM. All of those are just north of the battery, to the left of the PCM.
razrback
Full Access Members
I have an ‘03, owned since new, but unfortunately I’m not close to it to verify right now. I had this same issue once, don’t remember the fix. I replaced the AC years ago, and I remember the “T” vacuum connector fitting. Mine is an early ‘03, they made changes mid-year that complicated repair research, especially vacuum lines. Are you 100% sure the blend door is not the problem? Seems like there is one up under the dash, that was lots of fun to access. I’ll see if I can access my repair notes also. I wouldn't be to concerned about that screw/grommet thingy, pretty sure that is just holding that harness up.
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Hamfisted
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Yeah, somebody has done a hack job on your system. You'll probably have to search for another '03 or '04 in a salvage yard that hasn't been butchered and pull from that. I don't know what else to tell you.
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jamie1221
New Member
Mine is a 2000 expedition and had the same problem. It was a small leak in the plastic vacuum line that goes to a vacuum tank hidden behind the battery by ther fender. Quick fix. Don't know if that helps.
I don't know how I did it. But there's this little module behind the dash with a bunch of small hoses. The black one was cut. And the one on top I'm holding in the picture was disconnected somewhere under the dash. After days and days of trying I gave up, shoved the small hose in the big one and wrapped some electrical tape around it. The next morning I hopped in my truck and it was blowing out the front vents ice cold and changes direction perfectly. I have no clue where or how those 2 hoses are supposed to be hooked up but it worked.
Attachments
My only problem now is that when I hit the gas going any speed above 50mph it blows out of the floor for a few seconds then switches back to the front. I'm sure it's a vacuum leak still from the same area but I have no clue how to really hook it up or how it all is supposed to go.
Hamfisted
Full Access Members
Take a look at this vacuum diagram and see if you can come up with anything useful.
HVAC vauum diagram Gen2 EATC system
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HVAC vauum diagram Gen2 EATC system
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My '03 4x4 Eddie Bauer for the past 15 years has only blew out at the defrost. I discover that I was missing the vacuum line that goes through the firewall and going to The dash I wasn't n't going to pull the dash to run a new vacuum line
Hamfisted
Full Access Members
Scoot sometimes you're able to restore the dash vacuum by just sticking the plastic supply line back into the grommet hole.
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