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Discussion Starter #122
FPR has it's own vac line. However I guess the FPR could be going bad.

I also noticed a vac line was broken off this sensor and glued back on. Anyone know what sensor this is and if there is a USDM equivilent replacement? It sit under the BOV behind the intake manifold.

 

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Discussion Starter #123
Finally got the WRX brake booster hose on. It did help the idle problems, but it still surges at idle. But at least it isn't cutting off anymore. I haven't found any vac leaks yet.
 

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How bad is it surging? what RPM's is it fluctuating at? Do you have a vac/boost gauge? how much vac. is it pulling at idle?
Glad to here it's coming along though! :) I'm sure we can figure it out.
I'm assuming that you have new spark plugs, air filter, fuel filter already? Have you checked the resistance of all the plug wires for consistency?
 

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Discussion Starter #125 (Edited)
How bad is it surging? what RPM's is it fluctuating at? Do you have a vac/boost gauge? how much vac. is it pulling at idle?
Glad to here it's coming along though! :) I'm sure we can figure it out.
I'm assuming that you have new spark plugs, air filter, fuel filter already? Have you checked the resistance of all the plug wires for consistency?
It fluctuates between 500-800 right after I come to a stop. It will do that for a few seconds and then usually smooths out. Gauge tells me vac is 20 hg at idle, which stays constant. Plugs, air filter and fuel filter are all new. I haven't checked the resistence of the wires yet. Guess I will do that now.
 

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So it only fluctuates after your driving a bit and then come to a stop, but not right when you start it up and let it idle, correct?
And you have a good, constant vacuum, and no leaks. sounds like it may be hunting for a good afr at idle, maybe a front O2 going bad or a fuel pressure problem. Do you have any kind of fuel pressure gauge? Maybe you could hook up an in-line fuel pressure gauge (it's pretty easy and you can borrow one from vato zone, Just be careful!) to check fuel pressure at idle, just to see what it's at and if it's fluctuating with the idle. How about the fuel injectors? they could be gummed up or one could be fubar'd. I feel like we have to be getting close, there's not much more it could be! :lol:
 

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Hey sorry i didn't see this sooner, I'm pretty positive i know what your hunting idle problem is, We should have sent you a plastic piece that bolts to the front radiator support and runs to the snorkus in the passenger fender. In that plastic piece a small hole is drilled for for you to stick the intake temp sensor into. Iirc when i built your harness i left that sensor plugged in so I'm assuming you probably just left is hanging? Its important :) Pm me.
-Paul @ ECS Performance
 

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Discussion Starter #128
So it only fluctuates after your driving a bit and then come to a stop, but not right when you start it up and let it idle, correct?
And you have a good, constant vacuum, and no leaks. sounds like it may be hunting for a good afr at idle, maybe a front O2 going bad or a fuel pressure problem. Do you have any kind of fuel pressure gauge? Maybe you could hook up an in-line fuel pressure gauge (it's pretty easy and you can borrow one from vato zone, Just be careful!) to check fuel pressure at idle, just to see what it's at and if it's fluctuating with the idle. How about the fuel injectors? they could be gummed up or one could be fubar'd. I feel like we have to be getting close, there's not much more it could be! :lol:
Correct. It idles fine at start up. There is only one O2 sensor on this motor, so I will probably replace that also. I don't have a fuel pressure gauge. I was also thinking the injectors might be gummed. Is there any way to clean them?
 

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Discussion Starter #129
Hey sorry i didn't see this sooner, I'm pretty positive i know what your hunting idle problem is, We should have sent you a plastic piece that bolts to the front radiator support and runs to the snorkus in the passenger fender. In that plastic piece a small hole is drilled for for you to stick the intake temp sensor into. Iirc when i built your harness i left that sensor plugged in so I'm assuming you probably just left is hanging? Its important :) Pm me.
-Paul @ ECS Performance
I don't have the snorkus in my fender any more. So I installed the intake air temp sensor in the bottom half of my airbox? Will that be ok?
 

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Discussion Starter #130
Another piece to the puzzle. I noticed this morning on the way to work that even at a constant crusing speed I can feel the "hesitation". About every three seconds it feels like the motor doesn't get enough fuel for about a half second. I need to find a set of injectors to buy. Maybe that is my problem. After all of this though I can't afford to buy a set of new expensive injectors. So if anybody has a set they are willing to part with let me know.

Also, does anyone know what that sensor I posted above is and if there is a USDM equvilent?
 

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I don't have the snorkus in my fender any more. So I installed the intake air temp sensor in the bottom half of my airbox? Will that be ok?
I'm not positive that would work correctly. It may, but i would still like to see it in the stock location. Subaru' tend to run best in oem form. Just how they are, and why we have such success w/ our swaps.
-Paul
 

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I just did this same swap with a v5 STi ej207. I have a 01' RS and no snorkus, and in the fender there's just a flat plastic delete cover over the large hole there. There's a little hole just a bit in front of that cover that is just a tad larger in diameter than the IAT sensor. What I did was I wrapped the IAT around its middle part with some leftover rubber strap I had laying around and stuck it into that little hole in the fender wall so it fits nice and snug. It seems to work quite well.

I could take some better pics of it later this week, but you can see the line going to the IAT in these somewhat blurry pics from my thread. The line is the little black line going straight under the 2 coolant lines that come down from the manifold mounted reservoir on the passenger side. It goes straight into that little hole in the fender next to the covered big hole.





As for that really blurry pic you posted about the "sensor" with the broken off vac tube, I don't have anything like that on my engine, or at least that I can remember. From what I can see, it almost looks like an aftermarket boost control solenoid. But, it could also be the sender unit for an electronic boost gauge of some sort. What's the vac line coming out of it connected to? If it's going to the "T" in the vac line coming out of your BOV, or some other vac line going into your intake manifold, I'm almost sure it's the sender unit for an electronic boost gauge.

I did not know about the brake booster line with its check valve though. Is that going to be a big issue? My car idles nice and steady and runs smooth (and very quick) and I am using the stock RS line. Should I be worried about that?
 

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I didn't see problems until it started seeing alot of boost. I would get the line with the check valve, it's cheap and will prevent you from damaging your Vacuum Brake booster diaphram. It will also cure the weird brake pedal sensation while boosting. All in all it's a good idea and should improve the overall performance as well.
 

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Discussion Starter #135
As for that really blurry pic you posted about the "sensor" with the broken off vac tube, I don't have anything like that on my engine, or at least that I can remember. From what I can see, it almost looks like an aftermarket boost control solenoid. But, it could also be the sender unit for an electronic boost gauge of some sort. What's the vac line coming out of it connected to? If it's going to the "T" in the vac line coming out of your BOV, or some other vac line going into your intake manifold, I'm almost sure it's the sender unit for an electronic boost gauge.
That sensor is definetly not aftermarket. Look directly under your BOV. I can't remember where exactly the vac lines go (I'll look again later).

The surging is still there, but it seems to be getting better. I still have the weird hesitation when crusing also. I would like to pull the injectors and send them off to be cleaned, replace the O2 sensor, and maybe the fuel pressure regulator and see if that makes a difference. I'll start with the O2 sensor.
 

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Discussion Starter #136
That sensor is definetly not aftermarket. Look directly under your BOV. I can't remember where exactly the vac lines go (I'll look again later).
One vac line goes the the intake manifold. Smallest line pictured here.

The other line goes to a small metal line underneath the manifold that is attached to/runs parallel to the gas lines that run under the manifold.

Cubby, can you follow the line from your intake mani and tell me if your car has this sensor?
 

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Just got home and the engine is still pretty hot, so I peered under there just a bit.

You are correct, there is some kinda sensor there, but it's under this clusterf*ck of wires and vac lines in a very tight space, I can barely even get a glimpse of it. The only thing I can see without taking the whole intercooler off is a wire connector sticking out from under a bracket - I can only assume it is some kinda sensor. I can't even manage to see the sensor itself.

I can trace the vac line you circled back into that clusterf*ck and it seems to go into the area of that connector, but I'd still have no idea what that sensor is supposed to do.

I'd get a better look if I could take the intercooler off, but I won't have the time to do that until possibly this weekend. Hell, I gotta take off again in like 30 mins :(
 

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Discussion Starter #138
Just got home and the engine is still pretty hot, so I peered under there just a bit.

You are correct, there is some kinda sensor there, but it's under this clusterf*ck of wires and vac lines in a very tight space, I can barely even get a glimpse of it. The only thing I can see without taking the whole intercooler off is a wire connector sticking out from under a bracket - I can only assume it is some kinda sensor. I can't even manage to see the sensor itself.

I can trace the vac line you circled back into that clusterf*ck and it seems to go into the area of that connector, but I'd still have no idea what that sensor is supposed to do.

I'd get a better look if I could take the intercooler off, but I won't have the time to do that until possibly this weekend. Hell, I gotta take off again in like 30 mins :(
No need to take your intercooler off. I just wanted to make sure your V5 had that sensor as well. I am still trying to figure out what it is or a part number so I can order a new one. I will probably pull my intercooler off tonight and see if there is a part number on it.
 

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Discussion Starter #140
Here are a couple of new shots of the motor. Cleaned the motor up a bit and David (friend of mine) repainted the manifold while it was on the car!!

 
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