TwinTriangles

Ok all you simplified guys can you help me with 1 thing, I couldnt get the pic to post it was too big but there is two vac hoses on the inside of the Y-pipe outlet, one of which used to go directly onto the pressure chamber with a little check valve, now in the diagram its a orange/yellow vac line and it just shows it running off the Y-pipe but then just disintegrates into air, does that get blocked now ?
Thanks Yall
JDub

JONSKI

Just for reference, here's the complete vac hose diagram.
http://www.rpi.edu/~skrzyj/rx7/93vachosescolor.jpg

Here's a copy & paste from this thread:
https://www.rx7club.com/forum/showth...hreadid=167287


On Ribinette's site it says:
"11. The orange line that seems to go to nowhere goes to the upper intake manifold (it should be obvious, just thought I'd mention it before someone asked)."
(He means upper part of the lower intake manifold... Trust me. )

On the complete vac hose diagram, look at the light blue hose starting from the y-pipe. This hose then goes to a check valve, and then to the pressure chamber. What this is designed to do is simply pressurize the pressure chamber during boost. This pressure is fed to the Turbo Control solenoid (E), which is then used to operate the Turbo Control Actuator. In other words, this hose from the y-pipe is an important part of your sequential turbo system. Now look at the simplified vac hose diagram. Look at the yellow-orange hose. Again, the pressure chamber is connected to a check valve and the Turbo Control solenoid (E). However, in this diagram, the check valve hose starts at a nipple on the LIM. On the other side of the LIM is the corresponding nipple that connects to the y-pipe. This nipple and the three below it all go straight through the LIM, meaning they do not connect to the intake ports. Previously, this nipple was used for the EGR, but since it was eliminated, the author of the picture decided to use it to connect the y-pipe to the pressure chamber. Why did he decide to do this? Because the person moved their pressure chamber underneath the LIM to clean up the engine bay (click the pic of my engine bay in my sig). So, if you are going to leave your pressure chamber in the stock position, then simply don't use the LIM nipple. If decide not to use the LIM nipples for your y-pipe -> pressure chamber connection, then you don't even need to cap them, because they only connect to eachother and no pressure will be lost.

TwinTriangles

Okay jonski I see that there are 4 nipples on each side of the LIM The second one from the top on on the inside part of the LIM of the simp diagram now goes to the pressure chamber and the corresponding nipple on the other side of the LIM goes to the EGR, so your saying the inside nipple goes to the pressure chamber as shown in the diagram and the orange/yellow hose now goes to where the EGR line was right ?

TwinTriangles

BTW, Thanks a ton for being so smart & helping me with this... And I found my boost problem which I posted on a few days ago and just wanted to remind everyone to take your time when doing the Vac hose job & dont forget to replace any hoses like I did, I am now doing the job for the 2nd time & decided the simplification was a good idea...
JDub
Word of the day "Im an idiot"..."sometimes"

JONSKI

However you set it up, just make sure it goes like this:

y-pipe -> check valve -> pressure chamber -> TC Solenoid (E)

TwinTriangles

Gotcha, You've been a major help JONSKI, thank you.
JDub

Mindphrame

And for the LOVE OF GOD, remeber to connect the fuel regualtor.

Its not shown on the simp map. Use the actual hose diagram to see the mapping for that.

JPJ

I believe a lack of vacuum in the vacuum chamber may be a source of the turbo sequencing problems.

Can anyone answer a couple of questions pls.:

With the ignition off, I teed a vacuum pump into the vacuum chamber. The pump will draw 15+ in. of vacuum at this time, and it will hold.
I then turn on the ignition (engine not started). The vacuum drops off to zero.
Removing the pump, installing a vacuum gage, and starting the engine, the vacuum only goes to 5 in. -
even though the check valve that feeds this chamber will draw 15+ in.
What solenoid (or other device) opens when the ignition switch is turned on, which would possibly allow a leak, and the vacuum to not build up in the vacuum chamber?
Or is this chamber supposed to see only 5 in.?

If this chamber is supposed to see 15+ in. of vacuum, this loss is probably a source of troubleshooting the problem!