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Posted: Sat Nov 15, 2003 8:35 pm
by vrg3
Yeah, the fuel cut isn't just a threshold. In my experience, the ECU cuts fuel if manifold pressure exceeds about 13psi for longer than about 3 seconds. Spikes less than 3 seconds don't cause fuel cut.

Posted: Fri Jan 16, 2004 4:21 am
by J-MoNeY
You guys should make these cheap FCD and sell them to lazy clauds like me.

Posted: Fri Jan 16, 2004 4:32 am
by ciper
Thats sort of what Im doing, except its an electronic unit with many features http://bbs.legacycentral.org/viewtopic.php?t=14620

Posted: Fri Jan 16, 2004 4:44 am
by vrg3
$J-MoNeY-$ - You missed it; I sold the one I made in the Parts Shed. :)

Posted: Mon Feb 09, 2004 6:24 pm
by J-MoNeY
vrg3 wrote:$J-MoNeY-$ - You missed it; I sold the one I made in the Parts Shed. :)
:shock: :cry: .

THE END

Posted: Sun Feb 15, 2004 2:39 am
by Zadok
I figured out that if you just bore a small hole in the vacuum line between the pressure exchange solenoid and the pressure sensor, you can push back the fuel cut. That way the pressure sensor still reads vacuum and boost, but bleeds just enough boost to push the fuel cut back to 15+ psi, depending on how big the hole is and how much boost you wish to bleed off.
I found this is a little safer than a check valve because your no totally loosing all the boost that the car needs to see to adjust the fuel intake.

This is my last post on this board due to the ridiculous and overly rude & competitive attitudes people seem to have.
It's sad that all Subaru, and especially Legacy Turbo, owners can't have common curtousy and respect to want to help one another without the total disrespect that I see on this board and other Subaru boards.

Posted: Sun Feb 15, 2004 2:41 am
by ciper
Zadok: Im sure confused. I think you are alone with that idea, it seems obvious you cant understand the emotion behind the posts. Im probably the rudest person here and I have hard feelings only towards one person.

Re: THE END

Posted: Sun Feb 15, 2004 3:22 am
by legacy92ej22t
Zadok wrote:
This is my last post on this board due to the ridiculous and overly rude & competitive attitudes people seem to have.
It's sad that all Subaru, and especially Legacy Turbo, owners can't have common curtousy and respect to want to help one another without the total disrespect that I see on this board and other Subaru boards.
Wow! I totally disagree with you. I belong to almost every Subaru board there is and this is BY FAR the most easy going and friendly. I can't even fathom why you'd think that, except that you got a hard time about the car you have for sale. Nobody was rude about the rally tires were they? I also haven't actually seen to many post, if any (beside the above post), by you that weren't related to trying to sell something, so where did we fail to help you? Really, I don't see it.

Oh and I'm not knocking you at all but the above idea for getting around fuel cut doesn't sound like a good idea to me at all. All you're doing is creating a vacuum leak in your system.

Posted: Sun Feb 15, 2004 3:58 am
by evolutionmovement
I guess nobody here bought his car. :lol:

Steve

Posted: Sun Feb 15, 2004 4:36 am
by vrg3
Done right, the bleed can work. It'd be better than just using the check valve because it will allow the ECU to see some boost. It would be a small vacuum leak but that can be rectified with a check valve (making it just a boost leak), or could be small enough to ignore if you put a filter on it. Another advantage is that it can raise fuel cut instead of eliminating it.

Trouble is, it's hard to calibrate... to really know what you're doing to the signal you need to measure the effect it has on the transfer function when the engine is actually under boost.

Posted: Sun Feb 15, 2004 6:44 am
by legacy92ej22t
Ok, but why do that when you can run a vrg3 Phase II FCD. :wink:

Seriously though, I was so blown away by the attack against the board that I guess I didn't read it right the first time. I thought he was saying to put the hole between the manifold and pressure exchange solenoid, not the pressure exchange solenoid and pressure sensor. I can see how it would be nice to raise, instead of eliminate, the fuel cut. I still wouldn't do this myself though, it just doesn't seem like a real good idea when there are other low cost options available IMO.

Posted: Tue Jul 06, 2004 12:51 pm
by -K-
I just put another bleeder (next to the boost) valve with a one way valve to keep it from leaking. So it only vents pressure. I opened the pressure switch bleeder all the way, opened the boost one a little at a time untill I got the Boost I wanted, then closed the sensor one a little at a time untill I hit the fuel cut, opened it a 1/4 turn. That's it, not to hard to calibrate. :)

Posted: Sun Jul 25, 2004 1:56 am
by azn2nr
do you still get the corect reading on you boost guage if you do this fcd

Posted: Sun Jul 25, 2004 10:16 pm
by vrg3
As long as your boost gauge's signal line is tapped far from the leak (either very close to the manifold or -- preferably -- at another fitting on the manifold) it should read correctly.

my check engine light comes on and the car sputters

Posted: Sun Oct 03, 2004 5:23 pm
by TurboLegacy
i put a check valve in, and when i try to run the car at boost it, the turbo sputters and the check engine light comes on. anyone know why this would be?

Posted: Sun Oct 03, 2004 6:55 pm
by vrg3
What trouble code does the CEL show?

Where and how exactly did you plumb the check valve in?

Posted: Sun Oct 03, 2004 7:29 pm
by TurboLegacy
i dont know the code, the check engine light comes on. i put it in the exact same place as in the picture in the beginning of the thread.

Posted: Sun Oct 03, 2004 7:31 pm
by vrg3
You should read the engine trouble code. The computer will tell you why it turned on the check engine light.

So you put a tee in the vacuum hose going to the pressure exchange solenoid, and then put a check valve on the third fitting on the tee pointed to flow outwards?

Posted: Sat Oct 09, 2004 3:52 am
by TurboLegacy
OHHHHHHHH! i know where i messed up , i think. i didnt put a " T" in, just ran the check valve inline with the hose. i also have my boost gauge hooked up to that line right now, where else can i put my boost gauge line, i did have it hooked up to the pipe going from my intercooler to the throttle body. could you show me a picture of a better place to hook it up?

Posted: Sat Oct 09, 2004 4:32 am
by vrg3
Your boost gauge should still work okay on that line if you have it tapped close to the manifold.

Where to connect the gauge depends partly on what you want to read... Do you want to know compressor outlet pressure? Intercooler outlet pressure? Manifold pressure?

Posted: Sat Oct 09, 2004 4:47 am
by TurboLegacy
ill move it closer to the manifold, but that the problem right?

Posted: Sat Oct 09, 2004 5:05 am
by vrg3
But what's the problem?

Putting the check valve in the line to the sensor instead off a tee? Yeah, that's almost definitely a problem.

Posted: Sat Oct 09, 2004 5:13 am
by TurboLegacy
k, quick fix, thanks

Posted: Fri Jun 03, 2005 7:45 pm
by ej22t
Does anyone has the parts # that use on the one way check valve and also where should I got those parts for this DIY FCD?

Thanks for help

Ben

Posted: Mon Jun 06, 2005 3:04 am
by Navigator
Ben,

Talk to Nuwan, he has made a few, we just installed one on my legacy tonight and it works perfect. If you want send me a PM with your number and I will have him call you, his internet access is limited these days. You still doing the TSD's, we are planning for Tall Pines. :lol:



Ivano

Yes I now have a Turbo Legacy Too!!! :D