SO... Much... Fuel cut...

Headlights to tailights and everything in between.

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BAC5.2
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SO... Much... Fuel cut...

Post by BAC5.2 »

OK, this is weird. I installed the FCD that I got from Vikash and the MBC and IC and all that good stuff.

But there's a problem.

Aside from erratic boost (i.e. lots of boost creep, pulls at 9psi in 2nd, and but hits 12.5 all the way in 3rd and 4th), there is a fuel cut problem

At 12psi, in 3rd, at WOT, I get some fuel cut. If I don't go to WOT, but partial throttle it up there, it'll pull at 12.5psi no problem.

I don't think this is a problem with the FCD, but I don't know for sure.

Might this be a problem associated with the IAC code? Since it only happens at WOT. I can be boosting for a few seconds, then it'll cut, then it'll stay at WOT for a while, then cut, etc, etc. Is that overboost fuel cut? I am pretty sure I installed it correctly.

What do you guys think? If I didn't install it right, wouldn't the car run really shitty?

Stupid car :(
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[quote="scottzg"]...I'm not a fan of the vagina...[/quote][quote="evolutionmovement"]This will all go much easier if people stop doubting me.[/quote]
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Post by vrg3 »

Crap... this a lot like the kind of thing Matt sometimes experiences, isn't it?

Overboost fuel cut happens when you overboost for more than about three seconds.

It's hard to predict what installing the FCD incorrectly could do, since there are so many ways you could install it wrong :). But generally, I would say that installing it wrong won't make the car run poorly unless it also makes the ECU throw a CEL.

Like I said before, I don't know anything about IAC-related fuel cut.

Can you hook up the scan tool and see what the manifold pressure readings are like?
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BAC5.2
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Post by BAC5.2 »

Yea, I cut fuel every 3-ish seconds. Shit :(

Where can I unplug the other end of the connector from? It'd be nice to have the whole cable out of the car, so I can just solder it instead of doing in-line splices.
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[quote="scottzg"]...I'm not a fan of the vagina...[/quote][quote="evolutionmovement"]This will all go much easier if people stop doubting me.[/quote]
BAC5.2
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Post by BAC5.2 »

Another similarity to Matt's car that I have (the fuel cut thing isn't the same, mine does it all the time, I've never been in his car when it does it) is the hesitation I have.

I will be building to 8psi, and then as soon as it hits like 9psi, I get KICKED in the ass. It feels like a shit ton of turbo lag, but then it picks up at 9psi, and the turbo spools faster than you can blink, so I don't know what the deal is.
2009 Outback 2.5XT. 5MT. Satin White Pearl.
2009 Impreza 2.5i Premium. Blue.

[quote="scottzg"]...I'm not a fan of the vagina...[/quote][quote="evolutionmovement"]This will all go much easier if people stop doubting me.[/quote]
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Re: SO... Much... Fuel cut...

Post by legacy92ej22t »

BAC5.2 wrote:
Aside from erratic boost (i.e. lots of boost creep, pulls at 9psi in 2nd, and but hits 12.5 all the way in 3rd and 4th), there is a fuel cut problem
:(
Phil, that's normal. It's not boost creep really, it's that anywhere after 4800-5000k rpm the vf11 won't blow much more then 10-11 psi. When you're pulling in 3rd next time try to pull all the way to redline and you'll see what I mean. In first and second you run through the gear faster then the turbo spools or move into the high rpm's too quiclky to stay at the higher pressure. Boost creep would be more when you normally get 12 psi in 4th but the after you keep pulling for awhile it slowly creeps up another .5-1 psi.

About the fuel cut. When I have fuel cut problems it's severe and constant ( for the most part) it's just inconsistant when it will start acting up. When I do have the problem it acts a lot like yours except I'll get the FC at pretty much anything over 10.5 psi. It's not always a 3 second affiar either, it's more a high rpm thing. With mine I believe it was caused by my bad O2 sensor not throwing a signal when the ECU was seeing lots of air on the MAF and somewhat high boost at the manifold, thus causing FC. It very well might be that those connectors aren't good enough but you were already getting FC issues before, right? You weren't hitting 13 psi then either were you?

My car car shoots off after 9 psi too. I always figured it was a delayed timing and fueling issue.
-Matt

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BAC5.2
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Post by BAC5.2 »

:(
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[quote="scottzg"]...I'm not a fan of the vagina...[/quote][quote="evolutionmovement"]This will all go much easier if people stop doubting me.[/quote]
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Post by vrg3 »

You get fuel cut every time you hit full boost longer than 3 seconds? That means the FCD is either hooked up wrong or defective. The scantool might help figure out which...

The other end of which connector?

The varying boost levels are probably also partly a result of the cheap boost controller you have.
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Post by BAC5.2 »

The B48 (or whatever) connector that you splice the FCD into. If there was a connector a bit down stream it would make everything easier.

How is your boost controller any different than something from Joe-P or someone?
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[quote="scottzg"]...I'm not a fan of the vagina...[/quote][quote="evolutionmovement"]This will all go much easier if people stop doubting me.[/quote]
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Post by vrg3 »

Oh... The pressure sensor wires don't go through any connectors between the ECU connector and the connector at the sensor itself. Likewise for the MAF sensor (whose +12v supply you tapped).

If you want to install the FCD at the other end, under the hood, there are some general instructions linked to from the page: http://www.graphics.cornell.edu/~v/fcd/

That boost controller is pretty much the same as the Joe-P one... Joe P may have had more chances to select an appropriate spring or something, but it's basically the same.
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BAC5.2
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Post by BAC5.2 »

Well, a friend of a friend is coming up from Virginia, so I might have him solder it all up for me.

I don't want to twist and tape it, but I don't have the soldering skill to solder it myself.
2009 Outback 2.5XT. 5MT. Satin White Pearl.
2009 Impreza 2.5i Premium. Blue.

[quote="scottzg"]...I'm not a fan of the vagina...[/quote][quote="evolutionmovement"]This will all go much easier if people stop doubting me.[/quote]
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Post by evolutionmovement »

Only one way to learn. It's not hard anyway - even SM components are easy with the right stuff.

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Post by NemesisEJ22t »

BAC, i'm feeling the same 9 psi kick that you do, it only seems to happen sometimes though. As for wiring the FCD under the hood, i can send you a pic of my setup if you want, i didn't feel like trying to find the wires under the dash when i installed mine. I know it gets hotter under the hood than the FCD's circuit would like, but mine's been working fine for 2 months under those conditions.
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