skjerping@gmail.com

Hey there. I've got a 98 5.0 V8 Explorer XLT with 68k on it. I've got a
problem with heat and AC where, regardless of the
setting(heat/ac/floor/front vents/defrost), all air ONLY comes out of
the defrost vents up front. The level does go up and down(both fan
strength and hot/cold) when adjusted... basically everything works
normal except it only comes out of the defrost vents... very
frustrating. Any tips would be GREATLY appreciated. I'd prefer to fix
it myself if possible(I'm hoping it's just a disconnected hose or
something?). Any help would be greatly appreciated.

Thanks all!!!
Matt

JohanB

No vacuum , check for loose/broken vacuumhose under hood, passenger side


<skjerping@gmail.com> wrote in message
news:1138164405.088096.198630@g47g2000cwa.googlegroups.com...
> Hey there. I've got a 98 5.0 V8 Explorer XLT with 68k on it. I've got a
> problem with heat and AC where, regardless of the
> setting(heat/ac/floor/front vents/defrost), all air ONLY comes out of
> the defrost vents up front. The level does go up and down(both fan
> strength and hot/cold) when adjusted... basically everything works
> normal except it only comes out of the defrost vents... very
> frustrating. Any tips would be GREATLY appreciated. I'd prefer to fix
> it myself if possible(I'm hoping it's just a disconnected hose or
> something?). Any help would be greatly appreciated.
>
> Thanks all!!!
> Matt
>
>

Mikepier

I agree, vacuum problem. When it comes out through the defrost, it is
in "default mode", which happens when the vacuum does not work. Look in
glove box, there is usually a manifold with vacuum lines.

Steve Sigman

Mikepier wrote:
> I agree, vacuum problem. When it comes out through the defrost, it is
> in "default mode", which happens when the vacuum does not work. Look in
> glove box, there is usually a manifold with vacuum lines.
>

Dead on.. I just recently had this problem and ended up tracking it down
to one of the solenoids that control vacuum to lock/unlock the front
axle. This would of course only be on a switchable 4x4 (not AWD). the
solenoid had a hairline crack and was bleeding vacuum slightly enough
not to hear it but enough to cause the problem.
HTH

Steve