Wheres mah boost? please help diagnose bcs
 

Firstly i have done all the searches and i have read it all and replaced all my hoses etc (pill is in the line too) disconnected hoses and what not to diagnose so i have it down to a small section.

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[B]History[/B]

00 WRX with 3inch stainless TBE, STI computer (just hooked up by stechnic)

Car wasnt quick before...so i got the sti computer as a start to modding. After computer on the car felt more linear but no where near as quick. It didnt hit you in the back when you got on the throttle even at WOT. Now im wondering why everyone on here was saying the sti rexies hit hard when you get on it and why is mine so slow and getting overtaken by some family cars...

Installed a boost gauge this morning to see what was going. Unfortunately i didnt have one before so i dont know what psi it was running on stock.

took it for a spin its only hitting 6psi in all gears.

[B]Diagnosis[/B]

With all turbo/wastegate system correctly assemblies car only boosts to 6psi.

Ok so thats wastegate spring pressure

So i tried 3 things.

1. disconnect the boost control solenoid (BCS) electricals. That just caused engine light and car to fuel cut as soon as it hit 6psi.

2. leave it connected (electrically) and disconnect and block the 2 hoses that go to it. Still 6psi.

3. Take the hose off the compressor side of turbo and block it. Leave wastegate to atmosphere. WOHOO got some more boost now (using boost gauge i let off when it got to 10psi as i dont want to overboost and ruin it.)

[B]Problem?[/B]

So i would assume the BCS is stuck closed (blocking flow not bleeding) which is making the wastegate open at 6psi. Ive blow into it with the car on and off and its closed both times. I cant feel it operate either way.

Could this be because of the STI computer (the sti ecu is from the same model 00/99)?

OR just a failed BCS?? maybe these things die..it did have a fair bit of oil around the nipples.

Can i measure the electrical connection to see if its 12v or something to see if its getting a signal from the ecu? How else to diagnose why its not bleeding my flow to keep the boost up and away from the wastegate.


Thoughts??

Thanks guys any input would be great. Hopefully my post is in a logical order.
:Whdatk:

the boose olive is missing.

Please read.

[QUOTE]Firstly i have done all the searches and i have read it all and replaced all my hoses etc (pill is in the line too)[/QUOTE]

Its where it was before, inbetween the compressor and the T piece

connect the test connector under the steering column

if the boost solinoid ticks, then the tubes are hooked up incorrectly

Whats the test connector? Maybe i can connect my BCS directly to batter to see if it ticks as the soilenoid moves.

Im pretty sure all the tubes are hooked up correctly. I have a photo here if it makes it easier.

The waste gate goes the left of a T, the comressor to the right of a T the stem in the middle goes to the bottom nipple of the BCS.

[URL="http://www.localstore.com.au/stores/416/boost-juice/"]Boost Locations[/URL]

[URL="http://www.perth-wrx.com/vb/stock-ecu-discussion/30025-gc8-engine-control-unit-reset-proper-way.html"]test connectors[/URL]

Vac line runs:

[IMG]http://i311.photobucket.com/albums/kk459/t_racer69/SubaruBoostSystem_1.jpg[/IMG]

[QUOTE=ferozaj;669086]Whats the test connector? Maybe i can connect my BCS directly to batter to see if it ticks as the soilenoid moves.

Im pretty sure all the tubes are hooked up correctly. I have a photo here if it makes it easier.

The waste gate goes the left of a T, the compressor to the right of a [B]T the stem in the middle goes to the bottom nipple of the BCS.[/B][/QUOTE]

No it doesn't.

P.s Sti's also have much more responsive turbos....Better cams....better heads & different compression.

Seen that pic 100 times across the forums :P thats exactly how mine is connected.

Just had another breakthrough.

Connect BCS to battery and the solenoid moves and i can breathe through it.

Test the wiring plug that normally plugs there and it has 12v.

Plug the BCS back up to the connector....nothing..

Is it maybe too gummed up and it cant draw enough current through the ecu system to move??

I guess all of this can be solved with a manual boost controller which i was going to get but i want to get it running properly first.

-updated first post-

Is the MAP sensor plumbed in correctly?

Have you performed an ecu reset??? If not you need to. Refer to my previous post.

If AFTER you reset it you get a check engine light - refer to my link & read the codes to find out what is causing the ecu to go into limp mode.

P.s the ecu switches the earth side of any circuit it controls. Therefore there will always be 12v at the connector for any device the ecu drives when the ignition is on (like injectors & BCS for example).