stalkn_etsv8s

OK so here goes.....

I have followed the diagram found at

http://robrobinette.com/turbo_system_simplification.htm

Now my problem is when i take the car for a drive everything seems good,primary boost followed by hard hitting secondary boost But then out of nowhere primary boost disappears and car runs like crap. It also sounds like primary boost is venting out the charge relief valve but im not totally sure

After returning home i removed the vacuum line to the vacuum tank and heard pish like opening a bottle of coke. This lead me to assume the one way valve was stuffed allowing boost pressure into the vaccum tank.

Next i "tested" the one way valve by applying pressure with compressed air and holding the other side in a glass of water.
NO LEAKS

So what am i doing wrong?
My car runs PFC, stock turbos but have all the usual bolt ons.

Also to double check i have used the following connectors:
Turbo control - Tan plug
Charge control - White plug
Charge relief - Black plug
Turbo control - Odd black plug

stalkn_etsv8s

someone must have some ideas?

tt7hvn

iTrader: (5)

do you have the orange connector (pressure regulator control)? could be a fuel problem

try these:

stalkn_etsv8s

hey thanks for the pics,
i dont have the orange plug in use (PRC) as i am running an aftermarket reg

looking at your diagram it seems to route everything the same as rob robinettes but is drawn differently.

so frustrating!!!

tt7hvn

iTrader: (5)

that's the one i went by when i did my solenoid relocation, after i installed a pill that i forgot to earlier....everything work perfectly, 10-8-10 pattern

Banzai-Racing

iTrader: (11)

The mistake that we see most people make is that they think that the nipples on the inside and outside of the LIM are actual vacuum/boost sources. They are NOT, they are only pass-thru's. If you do not have the hoses connected to the corresponding nipples, you will have the problems that you are describing. The other major mistake that we see, is that people confuse the top two nipples on the outside of the LIM, the way that it is drawn the top nipple/hose is actually depicted as the second one down.

In NZ you will not have the top nipple that goes to the EGR, since I do not believe that you have EGRs. This means there will be only three nipples instead of four. You will have to route the hose around the LIM for the pressure chamber from the Y-pipe.

Hope that helps.

stalkn_etsv8s

Hey thanks heaps for the input, i have just double check my connections and i have the pressure chamber hose coming off the y pipe, i have the hoses connected as per the above drawing, 3 pass thru conections on lim from top:
dark green
yellow
light green

Is it possible that the one way valve to the vacuum chamber is leaking intermittently causing primary boost to only work sometimes? Does it matter which nipple on the uim i use for the vacuum chamber?

Thanks Tony

Banzai-Racing

iTrader: (11)

A problem with either of the 1-way check valves going to the pressure or vacuum chambers would cause problems.

tt7hvn

iTrader: (5)

+1 on checking your one way valves, pick up some viton ones and never look back

it would explain it, the charge control actuator needs both boost and vaccum to open all the way, if it doesn't get both of those, it only opens half way or not at all

tt7hvn

iTrader: (5)

or was it turbo control?

i can't remember, there are too many solenoids and actuators on this damn car

stalkn_etsv8s

amen to that!!

i have ordered a set of viton valves just waiting for them to arrive,i couldnt find anyone in NZ that had anything similar.

i hope it is just a dodgy one way valve sometimes working and sometimes not otherwise im at a complete loss

stalkn_etsv8s

ok heres the update....
My viton oneway valves arrived so i installed them and went for a drive

Primary boost comes on as it should,in any gear boost gauge goes nicely from vacuum into boost (about 12-14psi)
The problem occurs after hitting secondary boost,for example 2nd gear floor it primary hits 14psi followed by the secondary 14psi, hit 3rd gear floor it again seems fine. Select forth gear and accelerate moderately, NO primary boost. Button off completely and observe vacuum on the gauge for 3-5secs and primary boost returns to normal and stays that way unless secondary boost it reached.

This indicates to me a leaky one way valve however they are NEW and the Viton valves everyone recommends.

Help me please im going insane over here!

Mahjik

iTrader: (1)

Check this thread:

https://www.rx7club.com/3rd-generation-specific-1993-2002-16/weird-boost-issue-341534/

stalkn_etsv8s

hey thanks alot for the link, I've just read right through it.
First i tried swapping the 2 hoses to the turbo control actuator and ended up with no secondary boost at all so now im thinking Turbo Control solenoid?
Which can someone confirm is the Tan plug?