'88 boost solenoid valve questions

I bought a '88 TC last week for very cheap and finally have it up and running. The boost control solenoid valve and waste gate actuator had been bypassed leaving the waste gate fully open. Two lines from turbo inlet were both run to the BCS basically creating a closed loop that did nothing. One side of the tee connection from the compressor discharge was run to the WGA and the other was connected to a tee on the intercooler. I have no clue why they did this but the waste gate was held open and the turbo was pretty much bypassed. I noticed the BCS had broken tabs where the two halves are held together and dissasembled the solenoid to inspect. My question is this: The solenoid has two ports with one being open and the other containing a ball as a check valve of sorts connecting to the compressor outlet tee fitting and a small coil and pivot arm. My best guess is maybe there was a small spring at one time holding the arm against the ball causing it to vent the boost pressure back into the turbo intake port until the boost pressure overcame the spring pressure pusing the ball up and sealing the passage causing pressure to open the waste gate and the ECC can close the waste gate by energizing the coil and reducing the spring pressure as well. If I am even close to being correct then I am missing parts from the BCS mainly the spring? Can anyone tell me is my assumption is correct and a cheap easy fix to remedy this? I have ordered a boostvalve universal kit with 2-stage solenoid and would like to have the factory BCS to work for daily driving (when wife is driving) to help with fuel economy. Any tips or help is greatly appreciated.

Let me get this straight, your wastegate isn't connected to any vacuum source at all and you're still not getting any boost? If thats the case, fixing the BCS won't help you out, it sounds like your wategate has a broken spring or the actuator arm is disconnected from the flapper hinge.

Another possibility if you're using the stock gauge is that it is faulty or disconnected. Might wanna check that also.

Please forgive me if I have misinterpreted what you have posted.

The WG is closed by default unless the rod from the WGA breaks or comes unhooked. How the hose are connected doesn't change that. For how the hoses should be hooked up for a stock system see:
http://www.turbotbird.com/FAQpage/Vac_Diagram.htm

We have info on how the single stage gillis hooks up: http://www.turbotbird.com/techinfo/Gilli...sValve.htm

I haven't played with a 2 stage yet.
There is generalized info on boost controls here but I don't think it answers your question on the inner workings of the stock BCS. I never had one apart. I just throw in a Gillis and by pass the stock BCS. Sorry, I can't give you the specific answer you are looking for. Perhaps someone else can.
http://www.turbotbird.com/FAQpage/FAQpag...ls%20Works

I am thinking about trying to change my order to the two stage/two boost valve setup that way I can still get some power when playing with one valve and switch to the other for daily driving. Thanks for the help so far! I stink at trying to describe things but the waste gate was opening due to pressure where it was connected to the intercooler correct? As soon as pressure started to build it was seeing that actual pressure from the intercooler? I have it connected correctly now to the BCS and it does build pressure as indicated by the dash gauge but drops out very early after reaching around 6-8lbs at 4K rpm. The turbo spins freely by hand and has little to no vertical play and the same side to side and inspection after removal turned up nothing obvious as far as damage.

I think first I'd check your stock gauge's accuracy, then check the wastegate actuator. I've had two actuators fail on me and open too early, making full boost hard to reach. In fact, the turbo on my car now has a faulty wastegate actuator and I don't have it hooked up at all and I can't get much more than 19 PSI under full load. Under partial load I only see around 15 or so.

The stock gauges are known to not be accurate. The stock WGA are set to open at 9.5 psi +/- 0.5 psi.
Sometimes the WGA get weak and start to open at a lower pressure. You can check it by applying 10 psi if pressure. The rod should move just a few thousanths of an inch.

Have you checked the condition of the two big intercooler hoses. Take them off and check throughly for cracks. If good, then reinstall and make sure they are properly seated and clamped. The bottom one can be tricky and sometimes can get folded in on itself when the intercooler settles in.