BFGRX7

iTrader: (2)

I am disassembling my airbox to do the cheap bastard mod and noticed that two small tubes attached to the primary air tube (located just underneath the air pump) were not attached to anything! Now my 7's only mods to date are downpipe and HKS Twin Spark ignition and I've had a perfect 10-8-10 boost pattern since I've owned the car when there were no mods. These two tubes seem to be non-essential but If I look at this;

http://www.myrx7.com/oldsite/images/systemschematic.gif

I can follow the primary air tube and see that one of the tubes run to a pcv valve, the other to the...gulp...solenoid valve (wastegate control). Any advice would is greatly appreciated.

~Mike

BFGRX7

iTrader: (2)

^!!! Can anyone help me with this potential problem?

Narfle

iTrader: (16)

There are 2 big holes. I get the feeling you can sort those out. To the RIGHT there are 2 hose attatchments. BOV & CRV. On the LEFT there are two more. One facing up. One facing back. Back is the metal thingy near your airpipe. See it? Good. The one facing up is your air pump. Now it gets crazy. Your airpump has its own miniature airbox within the airbox! The last hose attatchment on the side is the airpumps cold air intake! Its supposed to go to nothing!

EDIT: That diagram you posted is absurdly confusing, and Im fairly sure you're reading it wrong.

Mahjik

iTrader: (1)

Use one of these diagrams:

http://fd3s.net/vacuum_hose_replacement.html

BFGRX7

iTrader: (2)

Barban, and Mahjik, thanks for the reply, but it looks like I'm not explaining myself all that well.

Barban, the issue is not with the airbox, it's with the primary pipe that leads to the turbo inlet. If you follow the primary pipe you'll see that there are two small tubes that are running off of that particular pipe. They are located directly under the air pump

Mahjik, looking at the first picture (after the three diagrams) in the link you provided, it shows the turbo control setup. My issue lies with the primary intake tube that cannot be seen in the picture but is situated JUST underneath that air pump.

Any ideas?

~Mike

Narfle

iTrader: (16)

My fault. I cant help.

Mahjik

iTrader: (1)

It is on the diagram. Look at the turbos, you'll see an 'A' on the front turbo. The primary intake elbow shows the two vacuum lines. It shows the green line which is used for the oil injectors. The next one is pink and is for the oil filler neck vent.

davesan1

iTrader: (4)

If I understand you correctly, you are talking about vacuum sized pipes. These are for very small diameter, (approx 1/4-inch) pipes which are black rubber on the stock car. There are two of these at right angles to the primary input hose. They "stick out" from the right-angled pipe that bolts onto the inlet manifold of the turbo. They are shown colored green and pink, respectively on the FIRST picture in the link that Mahjik sent you.



If these are what you mean, from memory:



I believe one of the pipes (the green one in the same diagram) is basically used to vent “used” control air. The Turbo Pre-control and Wastegate Control actuators are powered by high-pressure air from the primary turbo outlet. These in turn are controlled by individual solenoids. When these solenoids open, they bleed this pressurized air away, which disables the actuators. This air stream has nothing (directly) to do with the main air stream from the turbos. It is just a low flow control feed. However, this bleeding (!?) air has to go somewhere, so it is fed back into the inlet side of the turbo. I believe that it could equally well be just be allowed to bleed to atmosphere. Even though there is flow from the pipes continually whenever the solenoids are open, the flow is so small that it is unlikely to have any impact on overall boost. So, from a functional perspective, having this pipe missing is probably not a problem



I’m not sure where the second pipe comes from but it looks as if it may be used to pull gasoline fumes from the charcoal canister and then burn them – the diagram is not so clear on the pink pipe. If this is correct, if the pipe is not there it may impact emission control activity. THIS IS A GUESS, someone with more direct knowledge needs to pick this one up.


The only (slight) risk I see of the missing pipes is that it leaves the two small holes in the inlet. This in turn allows unfiltered air into the turbo. Dirt in the turbo is a no-no. However the holes are very small, but if you’re not going to replace the pipes I would at least plug the holes.

rynberg

Mahjik is the only correct one here. The two nipples on the primary turbo inlet feed the oil injectors and the serve as the crankcase ventilation. I would reconnect both.

davesan1

iTrader: (4)

Just seen Mahjig's second post. I believe that, in fact, the green pipe does both the solenoid vent job and the oil injector job. As for the pink pipe, I now see the "A" so ignore my guess.

BFGRX7

iTrader: (2)

Mahjik, Rynberg, I now see what you're talking about. The rubber hoses on those two tubes did not seem long enough to attach to stated points. Thanks for clearing this issue up for me.

~Mike