The flashed ECU is supposed to up the boost to a certain level per the computer.
I would rather have a MBC myself so I can manually adjust the boost when ever I want.

I have made this tool for testing many things it should work for you as well as long as you have a pressure guage on there that goes really low.
https://volvoforums.com/forum/volvo-850-16/home-made-special-tool-18124/

 

So compressed air is a must have?

 

Pretty much yes. A bicycle pump might work as long as you can hold the proper pressure.

 

Ok, ive got something rigged up, now, a bit of confusion, the chart you attached shows that my engine
( b5234t ) wants to see 12.5 kpa for proper adjustment.... which converts to 1.81 PSI... does this sound correct?

I think that since im using a basic vac/pressure gauge that the way I perform this test is a bit different. What ive got set up is a hand pump-> vac line>check valve> vac line> T fitting> vac/pressure gauge and more vac line to the WGA... What I read elsewhere was that about 5psi should start to open the WG, and 9-10 PSI should max it out...

Does this sound accurate?

In addition, after i set this per the above specs... I used the same gauge as a quasi boost gauge by running vac line into the cabin and it tells me that im going over 15PSI ( the gauge stops at 15psi and the needle is buried. So the good new is that it sounds like im in the good. ( but i wont be satisfied till my real boost gauge arrives... damn you ebay seller! )

 

Looks like you are getting closer.

 

Got my proper guage in there now... Definitely hitting good boost levels, but all based on how tight my WGA rod is.... And its a bit spikey and just slightly unsteady... No major loss of boost, but it doesn't plane out and stay even, its kindy wobbly... like it hits 14, lags, shifts, hits 15, then drops back to 14... unreliably at best.

So the question it, is my tightened WG rod a temp fix, that is masking an underlying problem?

At what psi should the WG start to open and at what psi is it to be fully open VS. how far should it actually open under load... ( trying to determine if i am stunting the WG from fully opening) but I guess it would be making more boost if it wasn't fully open theoretically.

 

Are you still running the 15G?
If so they are very unstable at WOT.
Also they are known to fade boost. Mine hits 14PSI and while still holding at WOT it fades down to 10PSI until it shifts then back to 14 and fades to 10.

I wish you could get the WG rod back to original and then go from there.

 

Yeah Still with the 15g... Thinking the turbo will be upgraded once I get all my suspension buttoned down.

When you say: " I wish you could get the WG rod back to original and then go from there" are you think, get the rod back to "factory" spec, then hunt down other issues? it really seems to me that that it was just outta whack to begin with and that i put it back to spec. That or, its all worn out and i was compensating for it with adjustment. I wonder if someone would be willing to measure the exposed threads on a bone stock WG rod to get an idea of where it "should" have started..... ?

 

Yes that's what I mean.

Also I wonder if one more thing is wrong.
A very common trate for the 15K is for the arm that the rod attaches to walks up and the round flap that seals everything up is moved up and it does not seal. That creates the low boost.

 

Hm, interesting, could i check for play up and down by grasping the "exterior flapper arm" and feeling? are you thinking that the WG flapper moves with it, causing premature wastegate leak OR, air is escaping from the turbo into the atmosphere via the hole where the flapper arm comes out?

 

Look where the arm goes into the housing. You will see a sleeve looking thing. See if there is any gap at all between the sleeve and the turbo exhaust housing. If there is try tapping it down carefully to flush and drive the car again and see if it is better.