Need A.I.R system removal tips... (sorry for askin guys)

[Archangel]

why would you use a spark plug if 5/8 bolts are cheaper, stronger, and easier to install in there?

[OVERKILL]

why would you use a spark plug if 5/8 bolts are cheaper, stronger, and easier to install in there?

I said in a pinch, IE, if you don't have any 5/8ths bolts.

[91LTDProject]

I looked over your supermotors site MLSC, and I must say it certainly looks alot better with all the vacumn line mess gone. I would like to do the same kinda deal, but I dunno where to start man. No clue. All those lines are so frekin ugly, and I accidently hit that big cluster of vacumn lines when I was pulling out the ac compressor, and it broke 2 of them, so they are in pretty crappy condition.

[gadget73]

They're all in crap condition. That plastic gets real brittle with age. Not much to be done about it short of replacing it with standard rubber tube. Hard plastic tube is waaay more expensive and you can't get it in fun colors. I used standard black tube and colored zip ties to mark them. I'm down to 1 smog line on my car, the red line to the EVR, and the green line from EVR to EGR. Stupid system still doesn't work correctly though so soon I might be at 0 lines.

[Archangel]

Aight, then we can lead you step by step:

1. behind the upper intake, the vacuum tree that sticks out has three branches - one fat rubber one and two tiny plastic ones, red in color. One of them tiny vacuum lines is pretty short, it goes from said vacuum tree straight to the left and to the fuel pressure regulator behind the throttle body - leave that one connected. The other red tiny vacuum line goes down and under the upper intake, then towards the front of the engine, and appears again near the oil filler neck of the valve cover - rip that one off, all the way from the vacuum tree where it starts from.

2. on the passenger side fender, find the three vacuum solenoids all the tiny vacuum lines connect to, rip all them lines out, completely.

3. on the front part of the EGR valve at the throttle body there's a single vacuum line, take that one out too.

4. on the passenger side of the engine, remove everything emissions related, hoses and valves and what not - after done you should only see the air pump down in the front, and the crossover A.I.R. pipe up behind the engine's heads. The air pump can be removed, but a shorter belt will be needed in order to still run the A/C compressor.

5. the crossover A.I.R. pipe has a one-way check valve where the rubber hose used to attach to it, if that is intact the whole deal can be left alone. Another option is to remove the air pipe, cut off the branch that has the one-way valve, then flip the pipe around and bolted back in so the holes in the engine's heads get blocked off by the solid faces of the blocks at the end of the air pipe. The cleanest solution would be to completely remove the air pipe, and plug the holes in the heads with either 5/8 bolts, or the special plugs designed for that, or even cut spark plugs as Overkill suggested. You must be aware that space between the heads and the firewall is pretty limited, and also the threads on the heads where the 5/8" plugs go in are usually pretty gunked up with carbon build-up, so be prepared to waste several hours to get the damn things done right.

6. by now yer engine (engine only, don't mess with the stuff on the firewall) should be free of all tiny vacuum lines and most emissions equipment. Now, remember them vacuum solenoids you pulled the lines off? There are two of them of about equal size, they are mounted on a common metal bracket, unbolt it off the fender and relocate it to a place where you can no longer see it easily, or any other place you desire - leave the wires plugged in tho, if you pull them yer ECM will throw codes. Now focus on the remaining vacuum solenoid, it's the biggest of them three, that's the EVR, the thing that tells the EGR valve when to open - move that to where you desire too.

7. time to re-run the vacuum lines - from the vacuum tree on the back of the intake run a vacuum line to the EVR on the fender, then another line from the EVR to the EGR pot on the throttle body. Yes, that's all the vacuum lines you need for yer engine to run correctly.

8. optional - on the fender there's a small vacuum canister, normally that's plugged in to the EVR valve too. Based on my experience with the big vacuum canister on the driver side fender (the "coffee can") I'm pretty sure it's not really all that necessary to have it, however if you feel like it you can plumb it back in the way it was stock - there's a one-way vacuum check valve somewhere in there too, so pay attention to that one too.

That's it, pretty much, any questions?

[Archangel]

Oh yah, forgot to mention that this past weekend the setup described above allowed my car to pull average 24mpg for the 130 mile trip to my buddy's place, and that included a 10-mile high-speed race with a cute girl in an S-10 Xtreme, and several pretty long WOT runs while passing idiots who were about to pass me

[91LTDProject]

Kickass, thanks MLSC. I like step by step instructions, make life much easier. Thanks for takin the time to type that out. I've been averaging 17-18mpg under normal mixed driving (bout half/half city highway), and have been keeping track of how everything I've changed has been affecting my mileage. Once again your guys help is appreciated.

[gadget73]

Take note where the two lines on the EVR go. The red one is manifold vacuum, green is to the EGR valve. If you hook the vacuum lines up backwards, you'll get a vacuum leak and the EGR valve won't work. I *think* the lower is source, and the upper is to the EGR but don't quote me on that.

[Tiggie]

Take note where the two lines on the EVR go. The red one is manifold vacuum, green is to the EGR valve. If you hook the vacuum lines up backwards, you'll get a vacuum leak and the EGR valve won't work. I *think* the lower is source, and the upper is to the EGR but don't quote me on that.

The exact problem on my '87 when someone did whatever they did in the engine compartment. I was comparing the the '87 to the '88 and noticed the lines switched. A quick look at the emissions decal got the lines sorted out.


Also everyone thanks for this thread. I am probably removing this mess on the wagon in the upcoming weeks so this thread is going to help me as well. This place is great!

[Archangel]

Soo, a little over a week later, how's the work going?

[91LTDProject]

Ummm, I didnt get anything done last weekend cause shit came up and I couldnt park the car. Was planning on going back to the track tommorow, but thats gettin pushed to next sunday now. I cant find a nice vacumn line kit in black, all they seem to sell is red around here. Got everything else. My 90 has the same plastic vacumn canister like you put on yours mlsc, how can I utilize it.

[Archangel]

which canister do you have, there are two - the big one on the driver-side fender (runs the A/C and cruise), and the small one on the passenger-side fender for the EGR stuff. The emissions canister has to be T-eed before the EGR, and there's an 1-way check valve between the canister and the T-ee, really the engine is supposed to sucks vacuum from both the EGR valve and the canister. I re-used one of the 2-to-1 rubber fittings off the stock emissions lines, basically I stuck it's fat single port on the EGR valve's inlet, and in the two small ports I plugged in the manifold and the canister vacuum lines respectively. As said before you can use rubber hose and regular vacuum T-ee if you'd like, reusing the stock rubber fitting is not necessary by any means.

[91LTDProject]

90's got the big plastic one on the drivers front fender, 88's got the juice can. Another thing I forgot to mention was than I'm having a hell of a time finding 5/8's bolts. Me and my dad found one browsing through the various heaps of hardware we have everywhere, but couldnt find another. gotta go to a special nut and bolt store downown and see if they got them

[gadget73]

Just remove the juice can and plug in the plastic one if you want to use it. Just a single vacuum port on the bottom of the box.

I got 5/8 bolts at Home Depot. They don't exist in really short form though so you're probably going to have to cut.

[Archangel]

I second on the coffee can, it has a tendency to rust out and cause vacuum leaks playing havoc in the HVAC, replace it with a plastic tank off a newer vehicle when you can get yer hands on one. As for the bolts, the shortest they come is 1", while you really only need like 1/2" long - one solution would be to cut them shorter but that's usually a royal pain in the ass cause them things are fat, what I did was screw a 1/2"-thick nut all the way till it bottoms out on the bolts head and then bolt that to the heads - worked alright, not too pretty but it gets the job done.