Re: 1989 Tempo GLS - Panel Vents/Vacuum Lines/HVAC Switch
I'm not familiar with your model, but I recently had a HVAC problem, in my
'98 Ford Club Wagon. I did NOT have to disassemble the whole dash. I did
have to do a lot of disassembly of the right part of the HVAC system,
Without studying your account in detail, I would encourage you to localize
your problem. Perhaps you have a bad vacuum motor. An experienced HVAC
person might come along here, if you are real lucky, and tell you where to
look. Absent that, you'll have to deduce the specific problem the old
fashioned way, scratching off some skin from your knuckles along the way.
Yeah, it's OK to temporarily open vacuum lines with a car running. However,
I would caution you against leaving your body in the way of a dashboard
airbag. It could ruin your whole day, if you get punched out that way.
You can buy a vacuum test kit, which has a "pistol-with-vac-gauge." You can
INDUCE vacuum with the pistol, by repeately squeezing. That way, you can
test vacuum motors.
Look for a bound flap, too. Maybe the actuator is OK, but it just can't
budge a flap that has lost its smooth operation over the years.
PS The blender door in my car was actuated with an electrical position
motor, not a vacuum-acutated motor. All other HVAC position motors were
"IceWizard" <firstname.lastname@example.org> wrote in message
> I have a 1989 tempo that suddenly decided to no longer allow air to
> come out of the panel vents. I did some troubleshooting, looked up as
> much info I could online and in Chilton's, and I'm currently almost to
> the point of completely taking the dash off. I'm hoping someone else
> with experience can help stop me from spending a whole day attempting
> Basically, air will only come out of the Defrost and Floor.
> -- If I choose AC/MAX AC/Panel Vents air will come out of the Window
> Defrost vent.
> -- If I choose Defrost it will come out of the Window Deforst Vent.
> -- If I choose Floor it will come out of the Floor vents.
> This happens for both heat and cold.
> I have come to the conclusion that it is either a vacuum problem or
> somehow related to the vacuum lines.
> Behind my glove compartment are 2 vacuum lines, one black and one
> white. They are both fastened tightly and do not appear to be
> leaking. I have not disconnected one yet as I am unsure of if that
> will cause any other problems. Is it safe to remove one of them from
> the connector while the car is running?
> If there are only two lines, would the Window/Floor switching seem to
> indicate that these lines are fine, or could one of them be the
> Also, has anyone ever pulled out the heating/ac control unit from the
> panel? I have the tools to remove my radio, and the unit has the same
> holes. I can pry it out a little with those tools, but I get enough
> resistance to be afraid to try to pull it out any farther. Does the
> switch (between various degrees of hot/cold) need to come out first,
> or is there anything I'll break by pulling this out?
> I just want some reassurance that I've tried everything I can before
> taking apart the whole dash. Any tips would be appreciated, including
> on if it's safe to disconnect one of the 2 vacuum lines behind my
> glove compartment while the car is running. I figure I could use my
> finger simply to check if any exchange is taking place.