EATC Vacuum lines at the engine compartment

[PeterP11c]

Hello,
I have a problem and need your help. This afternoon, I was doing a little engine cleanup, checking fluid levels etc. I noticed a missing vacuum line coming from the "Outside Recirc Door Vacuum Motor" and an empty plastic sleeve at the firewall indicating a passage of the vacuum line into the engine compartment. Then, I saw a group of rubber vacuum lines at the engine compartment corner besides the battery and the shock absorber housing. There is one black plastic cylinder attached to the compartment side with one vacuum line on the top and two small solenoids sitting next to it. Both solenoids have plastic sleeves at the bottom indicating a vacuum line attachment, but both are broken off. Like with all things Scorpio related, a problem pops up when you least expect it. Can you advise which vacuum lines goes where?

[brokencase]

Would a picture of my engine compartment help? Not sure I can get to it right away, maybe later this afternoon.

[PeterP11c]

Yes, please. I may also need to remove the battery in order to see where these lines run behind it.

[brokencase]

I don't know of any vacuum lines that go behind the battery. so I am sorry I am not pulling my battery.

Anyway, hope this helps. The vacuum line with the white stripe goes to from the EGR solenoid over to the EGR valve.

BTW, if you have open vacuum connections then the car must be running horrible.

[PeterP11c]

Hello,
Thank you for your picture. Looking at it, I see some design changes between your model and mine. The setup you show with two carbon canisters I also have in my Scorpio and that is not a problem. But if you look into the very corner of the engine compartment you could see a cylindrical container with round holes on the top and two small solenoids next to it with vacuum lines attached.
These lines belong the the EATC, which controls interior temperatures only. Since I don't use A/C, it wasn't on "my radar" so to speak. Over the weekend, I will take out the battery and get a visual on the lines and try to reconnect them on the trial by error basis. Will see what happens.
BTW, the car runs just fine, good idle, decent mileage.

[Ed Lijewski]

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[Ed Lijewski]

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YMMV

[PeterP11c]

OK, great. Our posts criss-crossed in real time. Comparing with your pictures, I have both lines connected to the black cylinder and the solenoids are also properly connected on the top. That leaves only one loose vacuum line with nowhere to go. Perhaps, it is the vacuum motor line that my mechanic disconnected while working on the heater core. Big step forward. Many thanks, Ed!.

Update.
Pulled the car from the parking garage to get a better visual. OK, I found out that the one disconnected vacuum line belongs to the left side solenoid. It has a plastic cap that shows a side hole from a broken snout which is still inside the line. Will need to pry it out from the line and glue back together. That mystery solved, I still need to find the missing line to the vacuum motor.

[brokencase]

I think you need the following diagram. The EACT is not mentioned so I suspect you are referring to the outside/recirc servo.

Keep in mind if you have a vacuum line not connected to anything then that is a potential vacuum leak, you may be thinking the car is running ok, but resolve that leak and you might be surprised at the improvement.

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[Ed Lijewski]

..., (^) however if the EATC remains set in non-recirc mode it doesn't command vacuum to be released to power the HVAC box vacuum motor, so no effect on anything. I assume Peter hasn't set the control for A/C in a while to consider choosing recirc.

YMMV

[PeterP11c]

How very true. I didn't use A/C in a long time. I live in a coastal zone, so there is no need for either cooling or heating for the most part of the year. The "recirc" mode, I don't remember ever setting it up. Looking at the Vacuum Diagram, there is a vacuum line connecting the vacuum motor with a vacuum solenoid. I checked with the Electrical Manual and it points to the solenoid being wrapped with other vacuum lines somewhere behind and above the battery tray. So, if I find one I should be able to reconnect them together. This afternoon, I am going take another look at the area and see if I can locate the solenoid.
Yes, I concur on the vacuum leak. It bothers me to see disconnected vacuum lines like that, so this becomes a priority for the upcoming weekend.

[Ed Lijewski]

With hood up on an '88 without the leaf catcher (or remove it if you installed one) you should be able to get a glimpse of the vacuum hose to the HVAC motor or where it passes (or should pass) through the false firewall.

YMMV

[PeterP11c]

You are right, but the vacuum motor has no vacuum line attached to it and the false firewall shows empty hole where the line should be. My only option is to find the solenoid being the other end of the vacuum line.

[PeterP11c]

Another update.
1. I went downstairs, pulled my car into the alley and took out the battery. There are 3 vacuum lines running behind battery strapped to the fire wall with two plastic clips.
2. By comparing the Electrical/Vacuum Manual and the Vacuum Diagram provided by Brokencase, I was able to name the 3 components sitting in the corner.
A. Black round cylinder with 2 lines on the top is called "Vacuum Reservoir".
B. Two small solenoids attached to the side wall are called respectively: "Outside Recirc/Door Solenoid" and "Hot Water Valve Solenoid".
3. The damaged snout belongs to Outside/Recirc Door Solenoid and the vacuum line should connect this solenoid and the Outside/Recirc Vacuum Door Motor.
4. I found the end piece of the vacuum line in question. It is impossible to see it unless you remove the battery from a tray.
5. Now, here it gets interesting. This vacuum line is split with a plastic reducer. One piece of larger diameter goes to the solenoid OK, the other piece should connect to the vacuum motor. But, I found a small plastic pipe 05" long sticking from the end of it. It is damaged with sharp object like a knife so I cannot figure what it looked like originally. The vacuum motor itself has a short metal pipe sticking from the housing so this rubber vacuum line should go in without any additional plastic attachments. This leaves me baffled.
6. The good news is all major components are still in place, only minor repair to one solenoid is needed. The bad news is some Electrical Manual diagrams are incorrect. Page 161, Diode C1901 is shown behind battery tray and I am pretty sure it sits atop evaporator case.
7. Finally and after all these years, I found a rubber trap door neatly attached to the fire wall behind the battery. I was able to scoop out some old leaves by pulling the rubber. Mind you my car didn't have the leaves mesh installed on the top as being made in 05/29/1987. So they installed this little device. Ingenious.

[Ed Lijewski]

But, I found a small plastic pipe 05" long sticking from the end of it. It is damaged with sharp object like a knife so I cannot figure what it looked like originally. The vacuum motor itself has a short metal pipe sticking from the housing so this rubber vacuum line should go in without any additional plastic attachments. This leaves me baffled.

No mystery. Find or buy some vacuum hose (sold at auto parts stores) that fits the vacuum motor nipple. Feed it back (you'll find a route through the false firewall) to the broken plastic nipple. Cut out that broken nipple and show it to an auto parts person (NAPA people are usually more knowledgeable about odd parts). Most auto parts stores have a section of odds and ends parts that might include what you need; you don't have to tell them what kind of car its from, plastic vacuum hose connectors are generic in a few sizes.

YMMV