Vacuum Hoses...My Head Is Going To EXPLODE

[amc78concord]

Well, after my new heater core was put in, I decided today to try to fix any vacuum hoses that might not be right...(which goes back to my lovely valve cover replacement pandemic).  So I took my Dad's MINT '87 Eagle Sedan and parked it next to my Woody wagon side by side so I could go from engine to engine to compare hoses...  AND WOW... there were SO MANY hoses that were completely put on wrong, and just some that didn't go anywhere in the thing.  Just the only the thing is that my Dad's '87 Sedan has a few different things than my '83 on a couple hoses.  Was the vacuum setup different from '83 to '87???  

On my '83 Woody Wagon there are hoses that come from the driver's side fender wall below the 4 wheel drive vacuum canister and I don't know where they go???   On my Dad's '87, there is plug right there where those lines would have gone through the fender wall... What the heck?  Then I notice that there is some round spherical looking thing next to the carb, and it has a vacuum line going to one of the holes in the air cleaner.  My '83 doesn't have that...

There must be a difference in how they ran the hoses...but I copied everything (the best I could) from my Dad's '87... and it runs LIKE CRAP... But yet, it seems to be a CONSISTENT running engine... it sounds like it has an over-sized camshaft in it and runs almost like a V-8....But when I put it in gear it doesn't want to stay running.  

So if I copied everything from my Dad's '87, shouldn't it run right?  It can't be that big of a difference...maybe timing needs to be adjusted? Because it was timed when all of the vacuum hoses weren't in their right (hopefully...) spots.

Can anyone possibly help me out here?

[IowaEagle]

There are differences between the years and even how they were equipped.  We have the engine vacuum diagrams for the different years/variations in the AMC Eaglepedia.   Please NOTE these are for the engines only, and do not include select shift, cruise control and other non engine vacuum connections.  You have stop and shift vacuum plumbing which is also different from your dad's '87 shift on the fly and I think you already found that plumbing to be different.  I believe we have the stop and shift diagram in another spot in the Eaglepedia.  And, it seems you have the variant where the vacuum storage canister, a metal one, prone to  rust, is inside your fender.  I have seen cars from the same years have this setup and ones like mine, an '82, which have the plastic one right next to the charcoal canister.  I don't think we have ever figured out why AMC did the metal one inside the fender and the rhyme or reason why you find different set ups on the same year cars.  At first we thought it was a Kenosha vs. Brampton difference, but I think we got that one disproved.

[thereverendbill]

what i am doing is gutting every vacuum hose I see with the exception of the vacuum advance.  Future plains is full time 4 wheel drive so i can make a patch panel for the dash.  the WRX killer will be born

[ammachine390]

Shouldn't your have a diagram under the hood on the emission control sticker?

[Jurjen]

what i am doing is gutting every vacuum hose I see with the exception of the vacuum advance.  Future plains is full time 4 wheel drive so i can make a patch panel for the dash.  the WRX killer will be born

Keep the one to the brake booster too, other wise you will have a TRB killer

[thereverendbill]

what i am doing is gutting every vacuum hose I see with the exception of the vacuum advance.  Future plains is full time 4 wheel drive so i can make a patch panel for the dash.  the WRX killer will be born

Keep the one to the brake booster too, other wise you will have a TRB killer

oh yeah, I forgot I kept that one too 

[Jurjen]

I threw many of them out, but kept some:
Advance mechanism
Brake booster
PCV
4WD
Cruise control vac canister
Heater valve vac canister
Purge canister

The dual CTO for vacuum advance by manifold to ported and EGR is gone.
So is the EGR and the smog pump system.

[amc78concord]

So the engine doesn't need all of these vacuum lines to run good?

[ammachine390]

While it technically doesn't need them, it won't run better than having them hooked up correctly, plus it will keep your emissions down, and your car won't be illegal.  I have all mine hooked up to factory spec and it runs great.

[amc78concord]

I made of video of my car and how it runs...I'm completely baffled.  Everything was put where it is SUPPOSED to go, all according to my Dad's 87 and then double checking with a vacuum diagram here from the Nest.  

Please take a listen, and tell me your thoughts.

Click this picture to view.


Also...about the hose that comes from the driver's side fender wall.  Where does it go? Can anyone shed some light on this, please?  I cannot find it on the diagram either... It goes through the fender wall and then is visible in the wheel well and it's going up to the front of the car.  Is it just pulling in outside air? If so, for what?

The hose, has a "Y-Connector" on the end to go to 2 different places...  


Where it goes through the fender wall below the 4 wheel drive canister


The other side of the fender wall, where do these lines go

[ericarmstrong]

Vac hoses comming from the fire wall will be for either the 4x4 shift motor, Air conditioning bypass, or cruise control.

[ericarmstrong]

Vac hoses comming from the fire wall will be for either the 4x4 shift motor, Air conditioning bypass, or cruise control.

You said fender wall not fire wall, sorry.

[IowaEagle]

The metal lines go to a metal vacuum storage canister inside your fender.  You have to pull the inner fender plastic liner out to get to it.  It could be one source of your problems if it is rusted out.  So your storage tank for 4WD is on that side?  Hmmmmmmmm, mine is on the  passenger side.

[amc78concord]

So your storage tank for 4WD is on that side?  Hmmmmmmmm, mine is on the  passenger side.

On my SX/4, it's on the passenger side as well..I just thought that was because it was a 4 cyl...

[IowaEagle]

One of those unexplained, yet, quirks about these cars.