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Topic: Heater Problem (Read 4554 times) previous topic - next topic

Heater Problem

Reply #15 –
Quote from: jpc647;303432
What vacuum actuator? I don't see anything labeled that. I was under the impression the line needs to be plugged in somewhere above the cabin air recirculation thing.


The actuator circled on the very left... That controls the flap between defroster vents and dash vents. It's pretty far up under the dash but you should be able to see it from underneath looking up from the right of the steering column. Each actuator has it's own separate single vaccum line. The yellow line attaches to the one on the left. The black with white stripe attaches to the one for air recirculation.

Heater Problem

Reply #16 –
Those are both connected. The black line in the glove box in my picture is what is unplugged. Its supposed to plug in somewhere near the brace for the heater box, according to the manuals. I just can't find it.



The line with the arrow pointing towards it clearly is the one unpluged. And it connects back into the plug thing that the circle is around. Anyone know where these is supposed to be connected to? The dash doesn't come out too too far, and its hard to see around in there. I looked where the manual said, but I'm wondering if it connects to another side of the heater box?

Heater Problem

Reply #17 –
Quote from: jpc647;303438
Those are both connected. The black line in the glove box in my picture is what is unplugged. Its supposed to plug in somewhere near the brace for the heater box, according to the manuals. I just can't find it.



The line with the arrow pointing towards it clearly is the one unpluged. And it connects back into the plug thing that the circle is around. Anyone know where these is supposed to be connected to? The dash doesn't come out too too far, and its hard to see around in there. I looked where the manual said, but I'm wondering if it connects to another side of the heater box?


I'll have a look on my car and get back to ya in a few minutes...

Heater Problem

Reply #18 –
Thank you. I'll be anxiously waiting for your discovery.

Heater Problem

Reply #19 –
Here it is! That vacuum connection pulled inside from the firewall. It connects to a vacuum valve under the hood on the passenger side at the cowl. You just need to fish it back through and reconnect it to the valve. The other vacuum connection on the valve goes to the vacuum canister inside the fenderwell on the passenger side behind the battery. The vacuum valve is fed by a vacuum junction on the driver's side of the firewall.

Heater Problem

Reply #20 –
Another aspect...

Heater Problem

Reply #21 –
Thanks for your help. I owe you a million. That has to be it.  The engine "rough" idle cleared right up when I put my finger over the plug on the valve. Thanks.

Just by chance, do you know what causes the heater control to not work when the dash it apart? I was going to test it but there is no power to the unit. Just curious, no big deal if not.

Heater Problem

Reply #22 –
Quote from: jpc647;303466
Thanks for your help. I owe you a million. That has to be it.  The engine "rough" idle cleared right up when I put my finger over the plug on the valve. Thanks.

Just by chance, do you know what causes the heater control to not work when the dash it apart? I was going to test it but there is no power to the unit. Just curious, no big deal if not.



Hey glad to help! I am also glad I helped you with the rough idle problem!

I am thinking since you have the dash torn out you may have no ground to anything that is installed in the dash panel. Most of the major grounds in the dash wiring connect to the metal frame of the dash, usually somewhere in the dash frame at the bottom rear inside of the radio/HVAC location, so when the dash is removed there is no ground because the frame of the dash is not in contact with the metal structure of the car.

Heater Problem

Reply #23 –
Thanks again. I had to stop for a while, its really cold out there. I think the bolt you disconnect under the instrument cluster might have something to do with it. Either way I really appreciate the help. I owe you one. I'll finish up the reassembly tomorow, its just too dark and cold to continue. :(

Heater Problem

Reply #24 –
wow,, i totally didnt mention the three way valve because i thought you already checked that.  that little animal is the main hvac vac source. it has its own little tank in the fender well as well.

Heater Problem

Reply #25 –
Alright. Maybe I'm mixing up vacuum canisters? In your second picture where it shows the strut tower, that vacuum line goes to which vacuum canister?  I can't find it in the car. Are there two in the fenderwell? The following picture used to be in the fenderwell of the v8 car when the motor was removed. I botled it to the strut tower just because it was easier.




The wire on my car that plugs into the same port of the valve enters the fender through this hole. I can't figure out where it goes from there, without taking the inner fenderwell off, which I don't want to do unless we determine something is routed wrong.



The vacuum line (wrapped in loom) from the "vacuum canister" I posted in the first picture goes into the bottom sensor that is bolted to the back of the strut tower(pass side). As shown There is a "T" here which splits this line. One line goes to the other side of the same sensor, and the other line goes up to the firewall through a blue cicular Ford check valve, and then connects to a spout on the back of the plenum, you know the thing where is says 5.0 on it. The line which is wrapped in rubber with ribs, dead in the middle of the picture, is the line that goes to the plenum.



So is this right? Where does the line entering the fender go? Its tight, I can't pull it. Is there another vacuum canister somewhere that I just don't know? Is the "vacuum canister" I bolted to the strut tower and actual vacuum canister? Is that going where it should?

Heater Problem

Reply #26 –
the one line going into the fender well leads to a vac storage container for hvac.

if you can suck on the line and it holds your tongue to it,, the canister is ok.

that 3way valve deal sources from the vac tree,
sorage to the vac canister
uses vac at your interior controls.

The round cylinder looking one you have a pic of does the same thing but is a vac storage for a few vac opperated emissions solenoids.

Heater Problem

Reply #27 –
They relocated the HVAC vacuum tank from down by the battery where Watchdevil's 84 has it ,to up closer to the fire wall where your 88 has it.

Heater Problem

Reply #28 –
so the thing I relocated is not the same.

Heater Problem

Reply #29 –
Quote from: jpc647;303559
so the thing I relocated is not the same.

The HVAC vacuum tanks that I am familiar with are spherical or ball shaped.
The one in your pictures looks like the one they use for other vacuum controlled stuff. Like the EGR and Thermactor valves.