Where does this vacuum line go?

[sd_iconoclast]

I am putting together a '92 DOHC that I have just rebuilt and I cannot figure out where this one vacuum line goes. It is a metal line that bolts to the fuel rail. One end comes out under the plenum just above the #1 cylinder. The other end comes out behind the dog bone bracket at the rear of the even cylinder head. Both end have barbs on then with short lengths of vacuum tubing still attached. Presumably, I cut the tubing when I pulled the engine.
Does anyone know what these two ends attach to?
Also, I have pulled three of these engines, and this tube seems to be plugged on all of them. I wonder if this contributes to any common problesm with the DOHC.

[brian89gp]

goes from the passenger side plug on the plenum to the vacuum modulator on the transmission.

[sd_iconoclast]

I guess I will not be needing this in my 5 speed Fiero then?

[brian89gp]

Doubtfull, unless you got one special 5spd

[pocket-rocket]

On the 5 speed cars, that port on the MAP sensor goes to the AIR injection setup, but who needs emissions equipment anyways?

[sd_iconoclast]

Here in the People's Republic of California, our glorious leaders make sure we have emissions equipment.
Are you saying that manual cars have air injection? I have never seen a DOHC with air injection. But I have never seen a manual car. In fact, I suspect that manual cars were very rare in California.

[sspeedstreet]

I'm doing a LQ1 Fiero 5-speed right now in California. Yes, they had an AIR pump. I looked long and hard before I came up with one. I've talked with a guy in Auburn, CA who has done or been involved with doing several DOHC installs. He said one of them passed BAR with the more standard Camaro-Firebird-Corvette unit installed.

[sd_iconoclast]

Could somebody send me a picture of what this air pump looks like. If possible, I would like to see a picture of it on the engine.
Does anyone know why the Manuals had it but the automatics did not?
Does it requier different intake manifolds?
Where in California are you?

[dykz34]

AIR injection equipped cars had different exhaust manifolds than non-equipped ones. AFAIK, that's the only difference (beside the actualy pump and lines, etc.)

[pocket-rocket]

Also, eventually all DOHC cars got it too. But I think the newer cars (IE non manual cars, so after 93 some time) did not have the lines in the exhaust manifolds. The intake manifolds are the same on the non AIR vs AIR equipped cars. I have been told that the AIR system is to warm up the catalytic convertor faster for emissions.

[qwikgta]

here is a pic of my 96 motor, i have plugged the AIR hole but this should give you an idea of what they are talking about

Rob

[Lyle's GTP]

Man that plenum is hugh, my 94 is not nearly that big. No way to easily change those plugs is there.

Lyle

[joey b]

easy, no it HAS to be removed. However, it is much easier to remove than on the 91-95

Also, where is the said hole for the AIR system that has been plugged?

[qwikgta]

Yea, just 7 bolts on the plenum and three on the side that attach the part that leads to the MAF you can have it off in 5 min easy.

The exhaust manifold has a large circle that is a plug in it. That had a large pipe that lead to the AIR pump. One on each side. I plugged it and then painted the mani's with high temp paint.

Rob

[pocket-rocket]

If I am correct, it would be the plugged hold beside the O2 sensor and the pipe for the EGR.