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Discussion Starter #1
Looked at some of the other misfire threads didn't seem to find one, quite like mine. 2012 been running fine for 60k miles cobb with stage 1 on it. Was driving to work and all of a sudden I got harsh studdering to the point of almost stalling. I limped it back home and today when I started it seemed to run better but definitely still something going on. Cobb said misfire on all cylinders and 2 more codes i really wish I had, they didn't have descriptions though. Talk to the local subaru repair shop(not subaru but all he works on) said possible timing belt, taking it back saturday and having him drive it hopefully he will know what is going on. Any help would be great though.
 

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Now a days a misfire of any sort is just broad. I think if you were able to tell us that what the other 2 codes were, im sure we could help out a little more. It is possible that the car jumped timing but i would think the belt or a cam gear would damaged if timing in fact was changed.
I would check fuel quality first. Its possible you could have gotten a really really bad batch of fuel. If possible try and get a fuel sample. Collect it in a clear jar and see if its contaminated with anything. If there is water in the fuel then it will visibly separate after sitting for a couple of mins.
 

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My personal guess is fuel pump if there have been no major changes, especially if it gets worse higher in the revs.

You should be able to Google the other two codes and see what they are also.
 

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My misfires were weird and went on for a year, I replaced the bpv gasket, and the y pipe gasket, new spark plugs, new tune. For there was another time my car sputtered and died and I would start it would idle rough and die. Didn't throw a code, a week later the same thing happened, driving 70mph on the highway my car shut off. That was the scariest thing I experienced in my car. I was stranded on the side of the highway for 3 hours. This time it throw a code and it was my fuel pump.

I had a friend who thought he had a blown turbo, so he bought a new turbo, here he had a blown off coupler. So problems are not always worse case scenario, it can be little dumb things.
 

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My misfires were weird and went on for a year, I replaced the bpv gasket, and the y pipe gasket, new spark plugs, new tune. For there was another time my car sputtered and died and I would start it would idle rough and die. Didn't throw a code, a week later the same thing happened, driving 70mph on the highway my car shut off. That was the scariest thing I experienced in my car. I was stranded on the side of the highway for 3 hours. This time it throw a code and it was my fuel pump.

I had a friend who thought he had a blown turbo, so he bought a new turbo, here he had a blown off coupler. So problems are not always worse case scenario, it can be little dumb things.
To bad you didn't have a fuel pressure gauge...You would have caught it alot sooner
 

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Discussion Starter #6
Sorry for late reply, I don't get on the internet much on the weekends, had the mechanic drive it he seems to think turbo. However when I build ~6 pounds of boost and then my a/f goes to ~20/1 which I know way too high, so I'm leaning more towards your guess of fuel pump, also through a bank 1 running lean fault code this weekend. Thanks for you the help:)
 

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Turbo???...I might look into another shop...none of the symptoms point to a turbo issue unless you are puking oil into the intake manifold.

Especially as soon as boost starts to build you go crazy lean, that screams fuel issues.
 

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Discussion Starter #8
Well just driving it feels like a turbo issue but I told him it was going way lean but he seemed to ignore mwith so fuel seems like a likely cause?
 

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Check fuel pump for proper voltages and resistance under certain loads. The accesport has a duty cylce for the pump it should. I'd check that out...

Did you happen to get a fresh tank of gas before this happened?
 

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I'd check fuel pressure. That will clear the whole fuel pressure system
Could be as simple as an air leak on the boost side of the FPR
 

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Discussion Starter #11
I think I'm going to have a smoke test done on the intake side before tearing into the pump, when you get on it I seem to hear air rushing that doesn't seem normal. I still find it weird that a post turbo leak would allow more air in, you would think you would lose pressure. I tried to do a data log of a/f and such but the cobb didn't grab it for some reason. Fuel pump was jumping back and forth between 33% and 67%. Might through in some water remover to the gas just to rule that out too, I ran about a half a tank before anything started happening but I'm sure stranger things have happened.
 
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