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VA Randy

The Dreaded "Defrost Only"

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Lots of discussion over the years about this, spent a couple hours reading and making notes. Have decent vacuum (16 psi) at the programmer, and all 4 colored vac lines hold vacuum when pumped up with the MightyVac, but no change in airflow from defrost. Seems like it's probably a mechanical issue. Saw pictures posted of the "flapper" door up high that may be the culprit, read that you could push a dowel through the center vent to move it, but that was probably on earlier years where there was a center vent. Looking at dash pictures, my '91 has a different layout, no vent at center, looks like it was moved to the right by 6-8 inches, so explains why I can't probe with a stick?  Looks like it's time to start stripping parts out of the dash for a better look. Got the holiday off tomorrow, so maybe can get somewhere with it. Any advice would be welcomed.

 

Also, saw pictures of a vacuum reservoir by drivers wheel well, and near the cruise control, this is also where my service manual shows it. After tracing lines, I found mine to be tucked away in front of the passenger wheel. Looks factory - tees off from near the AC line through firewall, short piece of rubber to hard plastic line that runs down passenger side, then back to rubber and under to reservoir.

 

After doing the vacuum tests on colored lines, thought a great troubleshooting tool for programmer issues would be an extra set of 6 inch lines with the programmer fitting on it, could then read vacuum while connected on each color to check if all internal solenoids were functional....

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Are you the person that I've been exchanging emails with about this problem today?

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Have seen that upper vacuum flapper get stuck, have to reach up high above the accelerator pedal, I usually bend the rod a little so it does not close quite so far.

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I think a worse case scenario would be the diverter door lever breaking.

 

Thanks to whoever supplied me with these photos!

 

Air Diverter Lever-2.JPG

 

Air Diverter Lever-5.JPG

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If all the vacuum is good i am betting on that lever being broke. It's almost a 2 hour job to remove the dash to get to it. 

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11 hours ago, Ronnie said:

Are you the person that I've been exchanging emails with about this problem today?

 Not me.

 

11 hours ago, padgett said:

Have seen that upper vacuum flapper get stuck, have to reach up high above the accelerator pedal, I usually bend the rod a little so it does not close quite so far.

Hoping it's as simple as this.

10 hours ago, DAVES89 said:

If all the vacuum is good i am betting on that lever being broke. It's almost a 2 hour job to remove the dash to get to it. 

Only 2 hours would be awesome, but we all know how it goes sometimes,,,,

 

Thanks guys for your thoughts, will update when I get in there.

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I wrote a tutorial about making a dash pad removal tool [it's on Ronnie's site]. I would advise that you take the time to make it otherwise you may end up with cracks in your dash top. I do have one or two of the levers you need as I pulled them from cars as kdirk and I parted them out. 

 One other thing as you enter into this project. When you remove the narrow vent plastic piece drill 3 holes in it to match up to the rear mounting screws. In the future if/when you have to go back in the top of the dash the vent plastic piece comes out with the dash pad saving you the risk of breaking the vent plastic. [I have extra of those as well as you may break in your first removal].

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21 hours ago, DAVES89 said:

It's almost a 2 hour job to remove the dash to get to it. 

 

If you're a magician, haha. Spent 4-6 hours today, almost there, looks like just need to lower the steering console and a few bolts.

Speaking of which, I'm thinking the dash should be clear once the column is lowered some (onto a box or something), no need to remove entirely?

Took out the drivers seat to make some room also, helped out a lot with moving around inside the car.

 

8 hours ago, DAVES89 said:

I wrote a tutorial about making a dash pad removal tool

I do have one or two of the levers you need as I pulled them from cars as kdirk and I parted them out. 

When you remove the narrow vent plastic piece...risk of breaking the vent plastic.

[I have extra of those as well as you may break in your first removal].

 

Saw the dash pad tool info and made something quite similar. The narrow vent piece had to be one of the toughest trim pieces I've ever removed.

May need a lever, should know soon when I get the dash off, had enough aggravation for the day and stopping where I'm at for now.

May be the weekend before I get back to it.

 

Thanks for the support and advice guys! 

Like I tell my crew at work, "Failure is not an option".

 

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There's a tutorial on Ronnie's site for dash removal. You might want to get familiar with his site. You do have to lower the steering column and we did remove the seats [me and another guy did this. We then reversed the nuts as the nuts have washers on them. Then I laid the floor mats on them to protect us.

 Be careful when you put the dash back in as we pinced a courtest light and kept shorting out the lights. We got real fast about R&R the dash, but we finally got it done.

 Drill 3 holes in that narrow vent to match the dash pad and you will never have trouble with the vent panel again...

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We all kinda knew what I'd find, didn't we.....

Now, is this thing pressed on? Tried a light pry with no movement, guess I'll pull the defrost section out and get a closer look.

 

On ‎7‎/‎4‎/‎2018 at 10:35 AM, DAVES89 said:

I do have one or two of the levers you need

 

I'd like to take you up on your offer if I could, will send message.

Crank.jpg

Edited by VA Randy (see edit history)

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You should consider reinforcing the new lever like forum member Machiner 55 did before installing it. I think he used JB Weld or something similar.

 

I hope John Doesn't mind me posting his photos. He is an asset to this forum but he doesn't come around much anymore.

 

GEDC0321.JPGGEDC0345.JPG

 

GEDC0347.JPG

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It's a press fit and will slide off. I have an extra one at my house and another at my buddy's house [He is a machinist and reinforced mine]. When I swapped put the dash on the Red I put in a reinforced one, but as I said I have another one.

 Now as I said on a prior post it is the time factor to get at one, not the value of the part.

 The part #3058309 on the one I have. The one one I have here is NOT reinforced. The one my buddy has is. He won't be back until Monday and neither will I.

Edited by DAVES89 (see edit history)

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