mystery hose

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Dec 1, 2006
Glenwood Springs, CO
hey guys,

i've got a mystery hose that i'm not sure where it's supposed to go.
it comes from the passenger side of the firewall and it has it's own opening.
the opening is about 5 inches below another opening that a bunch of electrical wire bundles come out of. this hose used to be hooked to the dizzy cap, but it didn't even fit right. i suspect that connection was a mistake. anyone know about this hose? thx!

the arrow in pic #1 is just showing the approximate point where the hose comes out of the firewall. the actual hose is not visible in pic #1 as it's kinda tough to stick a camera down there and focus.
has a metal nipple on the firewall right? (nipple :D)

that is for the distributor to vent. it was correctly set up.
i guess if you're de-smoging. I always left mine on with the 2f...
wonder if any other desmoggers have plugged that hose.
There are two hoses that might fit your description.
one comes out of a rubber gromit and bends down to drain condensation from the AC.
The other goes to a metal nipple, attached to a diaphragm, bolted to the firewall (with 2 10mm head bolts IIRC) that gives clean dry air to the dizzy from inside the cab.
It should not get removed for a desmog.
I've always seen that hose left attached to the dizzy for a desmog. I left it attached for my desmog.
did you perform the jim c. desmog, pafj?
Just talked to him about this the other day, it is definitely supposed to be there or you'll end up destroying your distributor.
i appreciate that fj60cam. but the schematic says different... and i believe jim approved it. don't know what to do, fellas, pls advise. thx!!
I am not sure that the schematic says different, as the diagram only shows the paths (tubes) to leave after the desmog. For instance (I think) the tube running from the HAC port on the carb (one of the four ports on the passenger side of the carb) and I think the port that is below the advancer port on the diagram (please correct me if I am wrong) is not shown in the modified diagram, and therefore can be removed (?) Also, the gas filter has two of ports blocked with a loop of tube. From the diagram it looks like there should be a tube running from the distrib. to the filter on the firewall, if not that tube and the filter would have been erased from the diagram.
here is the link for the Jim C. approved diagram:

the other link i posted earlier must've been an earlier version.

so here is how i am reading this diagram. this is why i am confused as to where the firewall hose goes...
the vac nipple and vac line on the distributor cap is a "breath tube". that tube or line goes to the vac fitting on the firewall that Kevin described above. The two vac lines on the side of the distributor (silver disks) are the ones that a desmog would "mess" with.
did you perform the jim c. desmog, pafj?

No... I just removed the EGR, and AI system-- and all associated crap. Removing these two pretty much wipes out all emissions stuff under the hood.

BTW this is done much easier with a manual at your side, but you probably already knew that.:)
I think the confusion may be stemming from differences between a 40 desmog and a 60 desmog.

Yes, you could take that hose, stick a filter on it and it would be just like the diaphragm (alla FJ40) or you could take that hose and stick it on the metal nipple (alla FJ60) which is like a filter that gets clean DRY air from inside the cab.
Seems like the key here is the DRY air. I would definitely keep it attached to the nipple. I think mine may be disconnected, and is probably the reason that it runs like s*** whenever it rains or gets washed etc. I need to check!
regardless of the diagram: the hose merely connects the distributor to a source of "clean/dry" air (the inside of the cab). There's no benefit to removing it, regardless of smog or desmog. It isn't part of the emissions control system.

It is only there to prevent moisture/dirt/gunk from entering the distributor.

You *could* pull it, but that doesn't net you any benefit and does increase the odds of your dizzy getting dirty/wet and not working.

You can argue all day about the diagrams, but in the end it is meaningless as on a 60, this hose has nothing to do with the diagrams.
And where did this diagram come from?
I do not believe this is for a 60, the advancer ports on the dizzy seem to be reversed, perhaps this should not be floating around unlabeled, a lot of people may end up with only 6 degrees of advance and then suddenly get 27 degrees when the HAC opens up.
There are 2 fittings on the dissy cap on all 78-newer Cruisers.
The larger fitting goes to the firewall filter.
The smaller fitting connects to the VCV as shown in post #13.

That is what the diagram shows, and that is how it works.

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