Cheap FCD

That spinning thing that makes all of the cool noises. OE and Aftermarket.

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vrg3
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Post 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.
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J-MoNeY
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Post by J-MoNeY »

You guys should make these cheap FCD and sell them to lazy clauds like me.
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Post by ciper »

Thats sort of what Im doing, except its an electronic unit with many features http://bbs.legacycentral.org/viewtopic.php?t=14620
vrg3
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Post by vrg3 »

$J-MoNeY-$ - You missed it; I sold the one I made in the Parts Shed. :)
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Post by J-MoNeY »

vrg3 wrote:$J-MoNeY-$ - You missed it; I sold the one I made in the Parts Shed. :)
:shock: :cry: .
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THE END

Post 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.
Last edited by Zadok on Sun Feb 15, 2004 2:42 am, edited 1 time in total.
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ciper
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Post 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.
legacy92ej22t
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Re: THE END

Post 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.
-Matt

'92 SS 5mt. All go and no show. Sold :(
'94 Audi UrS4 Modded (new project)
'96 Outback 5mt.
'07 Legacy 2.5i SE

[quote="Redlined"]
Oh... and I hope the fucker get bunked with Gunter, arrested for raping Gorillas.[/quote]
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Post by evolutionmovement »

I guess nobody here bought his car. :lol:

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vrg3
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Post 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.
"Just reading vrg3's convoluted, information-packed posts made me feel better all over again." -- subyluvr2212
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Post 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.
-Matt

'92 SS 5mt. All go and no show. Sold :(
'94 Audi UrS4 Modded (new project)
'96 Outback 5mt.
'07 Legacy 2.5i SE

[quote="Redlined"]
Oh... and I hope the fucker get bunked with Gunter, arrested for raping Gorillas.[/quote]
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Post 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. :)
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Post by azn2nr »

do you still get the corect reading on you boost guage if you do this fcd
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Post 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.
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TurboLegacy
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my check engine light comes on and the car sputters

Post 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?
92 legacy turbo 5spd fwd-12 psi, tm intercooler bov, walbro 255.

81 chevy malibu- 400 sb, holley 600, edelbrock rpm, hooker headers, lunati voodoo cam,4spd muncie, 3:73 posi,monte c. swivel buckets, corvette rally wheels
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Post by vrg3 »

What trouble code does the CEL show?

Where and how exactly did you plumb the check valve in?
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Post 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.
92 legacy turbo 5spd fwd-12 psi, tm intercooler bov, walbro 255.

81 chevy malibu- 400 sb, holley 600, edelbrock rpm, hooker headers, lunati voodoo cam,4spd muncie, 3:73 posi,monte c. swivel buckets, corvette rally wheels
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Post 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?
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Post 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?
92 legacy turbo 5spd fwd-12 psi, tm intercooler bov, walbro 255.

81 chevy malibu- 400 sb, holley 600, edelbrock rpm, hooker headers, lunati voodoo cam,4spd muncie, 3:73 posi,monte c. swivel buckets, corvette rally wheels
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Post 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?
"Just reading vrg3's convoluted, information-packed posts made me feel better all over again." -- subyluvr2212
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Post by TurboLegacy »

ill move it closer to the manifold, but that the problem right?
92 legacy turbo 5spd fwd-12 psi, tm intercooler bov, walbro 255.

81 chevy malibu- 400 sb, holley 600, edelbrock rpm, hooker headers, lunati voodoo cam,4spd muncie, 3:73 posi,monte c. swivel buckets, corvette rally wheels
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Post 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.
"Just reading vrg3's convoluted, information-packed posts made me feel better all over again." -- subyluvr2212
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Post by TurboLegacy »

k, quick fix, thanks
92 legacy turbo 5spd fwd-12 psi, tm intercooler bov, walbro 255.

81 chevy malibu- 400 sb, holley 600, edelbrock rpm, hooker headers, lunati voodoo cam,4spd muncie, 3:73 posi,monte c. swivel buckets, corvette rally wheels
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Post 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
92 Legacy turbo with EJ20G engine swap \(^0^)/
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Post 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
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