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fishawrx
09-16-2009, 08:46 PM
under wide open throttle, my car feels like the power just levels out at about 4k and up. It essentially feels like I don't have a turbo. I'm Still hitting target boost of 16.5 but running a little richer than usual at 10:1 instead of 11.5-11.8 to 1. Could this be a boost leak?

zone
09-16-2009, 09:04 PM
Maybe boost leak or Failing front 02 sensor maybe. Also check vacuum line going to the boost control solenoid.

fishawrx
09-16-2009, 09:44 PM
Maybe boost leak or Failing front 02 sensor maybe. Also check vacuum line going to the boost control solenoid.

checked the vacuum line, it appears to be in place. wouldn't the 02 sensor throw a cel if it was failing?

I may just have to hit up home depot and make a boost leak detector :twisted:

WRXNFX
09-16-2009, 09:47 PM
Maybe boost leak or Failing front 02 sensor maybe. Also check vacuum line going to the boost control solenoid.

checked the vacuum line, it appears to be in place. wouldn't the 02 sensor throw a cel if it was failing?

I may just have to hit up home depot and make a boost leak detector :twisted:

Clean your MAF maybe?

fishawrx
09-17-2009, 07:49 AM
that usually throws a code as well, at least the last time it needed cleaning. I'll check though.

I'm going to pull the intercooler and check the y-pipe connections, and the y-pipe itself. If this doesn't fix anything, I'll put a leak detector together.

cubedweller
09-17-2009, 03:10 PM
Leak detector? I'm curious.

fishawrx
09-17-2009, 03:57 PM
I've been reading up on these and please, someone, correct me if I'm wrong. Basically you get a PVC cap that fits over your turbo inlet, tap a air hose connect into the cap and pressurize the system using an air compressor. The fancier devices utilize a pressure gauge and a shut off valve so you know you're at least surpassing your target boost. then you can shut the valve and hold the pressure while you listen for leaks... w/o an aircompressor running in the background.

From what I've read, most people seem to put this device directly on the turbo inlet... which would be a huge pain on our cars. I'll either make the cap to fit on the end of my SPT intake or take off the SPT intake and fit it onto the turbo inlet pipe. I would just hook it up to the y-pipe (since the pressure side starts w/ the y-pipe) but it's pretty cramped for space under the intercooler.

fishawrx
09-17-2009, 08:08 PM
I tightened the intercooler to intake manifold clamp, the y pipe to turbo clamp and the bov bolts and... got my POWER back!!! easy fix.

WRXNFX
09-17-2009, 10:51 PM
I tightened the intercooler to intake manifold clamp, the y pipe to turbo clamp and the bov bolts and... got my POWER back!!! easy fix.


Cool.. 8)

zone
09-18-2009, 07:31 AM
:cheers:

fishawrx
11-21-2009, 04:30 PM
and now I've lost it again!!! took the intercooler out, checked all connections. the passenger side inlet to the intercooler had some oil around the connection, so I assumed it was leaking here. Speaking of oil, I might need a catch can. I emptied about half a can of brake parts cleaner into the intercooler to wash it out, came out pretty brown. And no, Subarus do not like starting when the intercooler is full of brake cleaner fumes.

Anyhow, cleaned everything, put it all back together, everything tight and still feel like I have a boost leak! My next guess is the y-pipe itself has a crack or something. i'm not throwing any CELs, so I don't think it's an O2 sensor. Might just order one of those fancy (ebay :roll: ) y-pipes and see if that helps. if that's not the fix, it's a little more eye candy w/ little to no performance value.

fishawrx
11-23-2009, 08:52 AM
found the fix this morning. Last week, when starting the car, there was a hitch in the starter and all of my electronics reset. turns out the positive battery cable needed to be tightened, did that then, problem fixed. When I thought about it, my "boost leak" started up around that time. Turns out, my ecu just needed to be reset! felt exactly the same as the previous boost leak that started this thread back in Sept. so that's what i set out to fix. Lesson learned, reset the gd ECU next time.

I am back at full power once again, very nice.

WRXNFX
11-25-2009, 11:39 PM
found the fix this morning. Last week, when starting the car, there was a hitch in the starter and all of my electronics reset. turns out the positive battery cable needed to be tightened, did that then, problem fixed. When I thought about it, my "boost leak" started up around that time. Turns out, my ecu just needed to be reset! felt exactly the same as the previous boost leak that started this thread back in Sept. so that's what i set out to fix. Lesson learned, reset the gd ECU next time.

I am back at full power once again, very nice.

Awesome, now lots of parts? :)

BTW Learning view can reset your ECU.

xI Light Ix
11-26-2009, 11:23 AM
LoL that is crazy. All of that from a battery cable. :wink:

fishawrx
11-26-2009, 11:57 AM
found the fix this morning. Last week, when starting the car, there was a hitch in the starter and all of my electronics reset. turns out the positive battery cable needed to be tightened, did that then, problem fixed. When I thought about it, my "boost leak" started up around that time. Turns out, my ecu just needed to be reset! felt exactly the same as the previous boost leak that started this thread back in Sept. so that's what i set out to fix. Lesson learned, reset the gd ECU next time.

I am back at full power once again, very nice.

Awesome, now lots of parts? :)

BTW Learning view can reset your ECU.

parts, oh yes. got the intake manifold off last night, cut out the tgvs. just need to finish smoothing up the tgvs, install the fuel rail and inlet and put it all back together.

i still can't figure out my power loss situation. once again, the car gets progressively weaker. then i reset the ecu, and it's back to normal. I think something needs to be adjusted in the tune. it seems like the ecu is learning off a clean slate (reset) and is adjusting for something wrong. it's just strange since I haven't had any issues w/ this tune until now, and it's been nearly a year running this tune.

ElScooby
11-26-2009, 12:16 PM
I would start logging like crazy and then start viewing what the data is saying. That way you might be able to track it down to a component that is starting to fail.

cseaman
11-26-2009, 09:06 PM
A failed front O2 sensor will NOT throw a code or a CEL, and it will make you run crazy rich. I would almost guarantee that's your problem. My car did the run shitty/run great (after you reset the ECU) thing for 3 months before the problem was narrowed down to the front O2 sensor.

WRXNFX
11-26-2009, 11:11 PM
parts, oh yes. got the intake manifold off last night, cut out the tgvs. just need to finish smoothing up the tgvs, install the fuel rail and inlet and put it all back together.

i still can't figure out my power loss situation. once again, the car gets progressively weaker. then i reset the ecu, and it's back to normal. I think something needs to be adjusted in the tune. it seems like the ecu is learning off a clean slate (reset) and is adjusting for something wrong. it's just strange since I haven't had any issues w/ this tune until now, and it's been nearly a year running this tune.

I have a guess, front O2 is bad, this is causing the IAM to cut way down, worse timeing, lower goost, etc.

ElScooby
11-27-2009, 10:50 AM
parts, oh yes. got the intake manifold off last night, cut out the tgvs. just need to finish smoothing up the tgvs, install the fuel rail and inlet and put it all back together.

i still can't figure out my power loss situation. once again, the car gets progressively weaker. then i reset the ecu, and it's back to normal. I think something needs to be adjusted in the tune. it seems like the ecu is learning off a clean slate (reset) and is adjusting for something wrong. it's just strange since I haven't had any issues w/ this tune until now, and it's been nearly a year running this tune.

I have a guess, front O2 is bad, this is causing the IAM to cut way down, worse timeing, lower goost, etc.

Doing some logging would probably help show a trend toward this being the issue. But the lower goost issue WRXNFX is talking about might be an entirely different animal, :lol:

WRXNFX
11-27-2009, 11:00 AM
Doing some logging would probably help show a trend toward this being the issue. But the lower goost issue WRXNFX is talking about might be an entirely different animal, :lol:


I give you goost!! :P

It is how Germans pronounce boost "juist" :lol:

ElScooby
11-27-2009, 11:23 AM
Doing some logging would probably help show a trend toward this being the issue. But the lower goost issue WRXNFX is talking about might be an entirely different animal, :lol:


I give you goost!! :P

It is how Germans pronounce boost "juist" :lol:

That's what I figured. :wink:

fishawrx
11-27-2009, 10:58 PM
parts, oh yes. got the intake manifold off last night, cut out the tgvs. just need to finish smoothing up the tgvs, install the fuel rail and inlet and put it all back together.

i still can't figure out my power loss situation. once again, the car gets progressively weaker. then i reset the ecu, and it's back to normal. I think something needs to be adjusted in the tune. it seems like the ecu is learning off a clean slate (reset) and is adjusting for something wrong. it's just strange since I haven't had any issues w/ this tune until now, and it's been nearly a year running this tune.

I have a guess, front O2 is bad, this is causing the IAM to cut way down, worse timeing, lower goost, etc.

Doing some logging would probably help show a trend toward this being the issue. But the lower goost issue WRXNFX is talking about might be an entirely different animal, :lol:

my boost is fine, still hitting peak boost, just feels like a boost leak. definitely starting to think that it's the 02 sensor... but I'll have to wait to hear back from AP so I can get my car running again.

fishawrx
11-28-2009, 04:04 PM
does anyone happen to have a spare, functioning o2 sensor that I could borrow for a day or two to see if it is indeed the o2 sensor going out? I just don't want to buy a brand new o2 unless I have to.