99 is blowing hot air only

[expe1969]

We recently had the 99 expedition in to charge the AC and
to try and diagnose the stalling (idle) problem that I see everyone has been having. After leaving we noticed it was still blowing hot air
out of the vents and no cold air.

Anyone know what is going on here? My mechanic
said he thinks the flaps on the controls are stuck...not sure
if this is the case? Thanks for you post. Glad to have found this site.

Eric

[sjschweitzer]

We are having the exact opposite problem with our 1998 Expedition. We have cold air and no hot. I tore apart the entire dash, took about 2 days, and found that the blend door was working fine. It was located basically behind the glove box. But the only way to get to it is to remove the entire dash ("instrument panel"). If you are getting lukewarm air with the fan on low and when you turn the temprature control to hot and the air turns hotter, it is probably not the door. Other than that, ours is still not working either. We are going to try replacing the vacuum control switch (the controller that you use to change the outflow of air from floor to defrost to panel etc.). We'll see if that does it.

[akader]

I had a simular problem with my 98 EB and found that the vent system works on vacuum. The Exp uses hard and rubber vacuum lines in the engine compartment. The control line for the vent flaps had a small in hole in the line. I recut the line and re-seated the line in the connector. This was located near the passenger side of the engine compartment on the firewall. It was a vacuum distribution port.
Alex

[expe1969]

Thanks akader. It appears these trucks are having the
same issues...all around. We brought it down to have them work on it
today and my mechanic agreed 100% with what you said.

While we're at it, the parking brake light is stuck on,
the abs light in on (which I was told is just a sensor) and
the drivers side heated seat doesn't work.

140k on our 99 truck now, how bout yours?

The tranny and engine run great. The alternator burned out
at about 135k, but that was too easy. My wife pulled into a garage as the thing blew out with the lights flickering and the guy had it done
in 45 minutes.

Thanks again,

ET

[akader]

I can't complain about mine. It has actually run without any problems since I bought it used at 35,000 miles. It has 110,000 now. I do about 90% of the maintenance myself so that I know what to expect when it does show signs of impending doom...
Alex-

[iarobj]

Man this site is great!! I am also have the same heating problem with my Expedition. I was told it may be a blend door and started to remove the dash, unfortunately I didn't realize what a task this would be and had to stop due to lack of time. I will attack it again but first I will check out the other suggestions. My A/C compressor just siezed as well, which sucks because I just had it replaced last year and of course the warranty just ran out. Is it difficult to replace the unit? One more thing.... Whenever my truck down shifts or when I reach 80mph the headlights dim significantly... any suggestions??? It is too bad I am having all these problems, I really dig my Expedition.

Thanks in advance for any help,

Rob

[strap21061]

Originally Posted by akader

I had a simular problem with my 98 EB and found that the vent system works on vacuum. The Exp uses hard and rubber vacuum lines in the engine compartment. The control line for the vent flaps had a small in hole in the line. I recut the line and re-seated the line in the connector. This was located near the passenger side of the engine compartment on the firewall. It was a vacuum distribution port.
Alex

The location of this vacuum distr port is where on the firewall? Is it by the heater core lines?
Thanks

[way2old]

This last post in this thread is over 3 years old. I don't think they will answer here. Please start a new thread with your problem. I am going to lock this thread.