Mysterious Vacuum Lines

[LongHorn]

That's exactly the problem! I have no idea what a stock vehicle SHOULD look like, so I don't know what's missing and what is not.

I think it's entirely possible that one of the POs started to strip-off some of the emissions gear, but not all of it. So, that leads me to wonder if part of the engine problems are due to the ECM (which I think is still hooked up) not controlling the engine correctly because some of the stuff is gone?

Most of the people on this forum have dumped the stock ignition & gone with a variety of options.
Popular are: The Team Rush, HEI & MSD. You can then junk the factory junk ECM.

 

[LongHorn]

This link breaks it down to 3 diagrams
Vacuum Details

I was looking at the link provided by Dslywalker & noticed this page:
AMC 258CID I6
It's a engine bay picture I think you'll find informative.

 

[66cj5a]

The two empty spots on the air cleaner look to be a temperature activated switch. It opened or closed off vacuum to "stuff" as the engine warmed up.

 

[Sasquach]

I was looking at the link provided by Dslywalker & noticed this page:
AMC 258CID I6
It's a engine bay picture I think you'll find informative.

Kinda scarry looking! Nasa would be proud of that!

 

[dslywalker]

Damn it was sure nice to throw that away
Mike

 

[MDJEEPER]

I was looking at the link provided by Dslywalker & noticed this page:
AMC 258CID I6
It's a engine bay picture I think you'll find informative.

This picture is informative. Thanks!

Well, it's obvious that my Jeep is missing various pieces, including the bank of vacuum solenoids that sit by the breather, the thermal electric switch, the thermal vacuum switch, and the pulse air intake tubes. I also don't see a decel valve or a manifold heater switch. And that was with a quick look! Who knows what else may be missing!

Also, as far as I can tell, the ECM is still connected to the distributor.

So, with this stuff missing, is there even a possibility that the ECM could even begin to control the engine correctly??

 

[Sasquach]

This is what is so appealing about going EFI, the MPI system eliminates all the vacumm control garbage and keeps you smog legal
while making your AMC 258 i6 / 4.2l run like never before.
The big drawback is it costs as much as you may have paid for your Jeep.

 

[MDJEEPER]

So, what do you think the chances are that I would even be able to find all of the parts and pieces needed to make the ECM system fully functional again?

Aside from that, it appears my options are:

1. Do the Nutter Bypass
2. Install a completely different ignition system
3. Try to make it work as best it can as it is with those various pieces missing (at least until such a time that #2 & $$ is a possibility)

Thoughts??

 

[LongHorn]

So, what do you think the chances are that I would even be able to find all of the parts and pieces needed to make the ECM system fully functional again?

Aside from that, it appears my options are:

1. Do the Nutter Bypass
2. Install a completely different ignition system
3. Try to make it work as best it can as it is with those various pieces missing (at least until such a time that #2 & $$ is a possibility)

Thoughts??

What I did was the "Total Swap".
Mallory Ignition 8560001C - Mallory 85 Series HEI Distributors - Overview - SummitRacing.com
I went HEI, because it was a simple & cheap solution.
Some say the "Nutter By-Pass" is cheaper.
In m situation, my distributer was bad.
So HEI was cheapest for me.$179.95 Summit Racing.

 

[Sasquach]

So, what do you think the chances are that I would even be able to find all of the parts and pieces needed to make the ECM system fully functional again?

Aside from that, it appears my options are:

1. Do the Nutter Bypass
2. Install a completely different ignition system
3. Try to make it work as best it can as it is with those various pieces missing (at least until such a time that #2 & $$ is a possibility)

Thoughts??

Excuse me if stated but do you have to smog test?

Can't say for sure on yours but with mine some/most of the emissions stuff is not available any longer so you would almost surely have to make it run the best you can with what you got.
The key is do you have to smog test an 86 in your state/county?

 

[dslywalker]

www.rockauto.com carrys some of them.Time you tally up the price you could probably do a nice upgrade.As mentioned before depends on emissions in your state.If not needed go for the upgrade.There's a lot of upgrades that are smog legal too.
Mike

 

[MDJEEPER]

No, this vehicle is not required to be smog tested.

Ideally, what I would like is something simple that can get it running pretty good for now. I'm thinking of waiting on switching to EFI or some other complete ignition upgrade until the engine is rebuilt. I was hoping to get another year or two out of it before the engine transplant...

 

[Sasquach]

No, this vehicle is not required to be smog tested.

Ideally, what I would like is something simple that can get it running pretty good for now. I'm thinking of waiting on switching to EFI or some other complete ignition upgrade until the engine is rebuilt. I was hoping to get another year or two out of it before the engine transplant...

Well that's good news! If it were me I would start pulling that junk off tonight and get down to the basics.
EFI would be great but you should be able to get it running pretty descent as a carbureted engine. I have eliminated my air pump completely, the EGR system is dead, the cat is gone, etc. but I'm Ca. and smog tested, I plan EFI for that reason as well as better running.
You want to keep the PCV system in basic form, maybe the evaporative fuel canister, obviously vacumm to your distributor. so much of those vacumm controls are absolutely nuts!

 

[MDJEEPER]

Well that's good news! If it were me I would start pulling that junk off tonight and get down to the basics.
EFI would be great but you should be able to get it running pretty descent as a carbureted engine. I have eliminated my air pump completely, the EGR system is dead, the cat is gone, etc. but I'm Ca. and smog tested, I plan EFI for that reason as well as better running.
You want to keep the PCV system in basic form, maybe the evaporative fuel canister, obviously vacumm to your distributor. so much of those vacumm controls are absolutely nuts!

Based on this, are you recommending the Nutter Bypass??

 

[Sasquach]

Based on this, are you recommending the Nutter Bypass??

Not familiar with the NB because it does not apply to my year AMC 258 i6 / 4.2l .
You should probably start a new thread a little more related to removing smog gear and what's really needed etc. There may me some more readers out there with good advise that are not following a vacumm line thread. Just an idea.

I wish I did not have to smog test.