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Old 02-11-2013, 02:12 AM   #1
Zondacl2
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PWN3D Misfire #1&3 when under boost

Hello to all, heres my issue, i live in NYC, unfourtunatly after this fuel crisis from the hurricane (sandy) I got fuel from my job, as desperate as we all was for fuel i took some.I added octane booster to be on the safe side (which is prolly BS anyways) but Only god knows wtf was in that fuel or where it came from. But shortly after i was gettin code misfire on #1 &#3 And even #4 at times. But she will idle fine and run great. Only when i push it and goes past 8psi in boost it starts to buck and bogg and not go past that point. She will try and jump to 9 or even 10 at times. Anything below that smooth no problems at all, car starts up fine, no high oil consumption or burning.i can cruise at 70 even 80+ as long as is i dont pass 8psi. (i try not to push it keeping below that magic boost number to avoid further damage) Looked for boost leaks all lines look fine. I tried a 2 bottles of fuel injector cleaner (which i F'in hate cause i know to much of that crap is no good) no help.Cleaned MAF sensor, just changed my radiator so kinda rulling out head gasket found no oil in anitfreeze, any ideas like fuel filter/injectors or plugs or coils or even boost leak? Ive been reading a lot on ringlands and i hope to god it isnt but anyone out there ever heard of a similar symptom i have? No crazy mods engines pretty much stock. Wish i could rule out plugs or coils but to freakin cold for simple ***** like that lol, just hoping someone can point me in the right direction who expierenced or herd of a simliar situation.
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Old 02-11-2013, 02:38 AM   #2
Uncle Scotty
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Originally Posted by Zondacl2 View Post
Hello to all, heres my issue, i live in NYC, unfourtunatly after this fuel crisis from the hurricane (sandy) I got fuel from my job, as desperate as we all was for fuel i took some.I added octane booster to be on the safe side (which is prolly BS anyways) but Only god knows wtf was in that fuel or where it came from. But shortly after i was gettin code misfire on #1 &#3 And even #4 at times. But she will idle fine and run great. Only when i push it and goes past 8psi in boost it starts to buck and bogg and not go past that point. She will try and jump to 9 or even 10 at times. Anything below that smooth no problems at all, car starts up fine, no high oil consumption or burning.i can cruise at 70 even 80+ as long as is i dont pass 8psi. (i try not to push it keeping below that magic boost number to avoid further damage) Looked for boost leaks all lines look fine. I tried a 2 bottles of fuel injector cleaner (which i F'in hate cause i know to much of that crap is no good) no help.Cleaned MAF sensor, just changed my radiator so kinda rulling out head gasket found no oil in anitfreeze, any ideas like fuel filter/injectors or plugs or coils or even boost leak? Ive been reading a lot on ringlands and i hope to god it isnt but anyone out there ever heard of a similar symptom i have? No crazy mods engines pretty much stock. Wish i could rule out plugs or coils but to freakin cold for simple ***** like that lol, just hoping someone can point me in the right direction who expierenced or herd of a simliar situation.

you very likely have crap in the tank that has fouled the fuel filter...and possibly fouled the injectors

do NOT beat on the car until you get this figured out as that may KILL IT when all you now need is a new filter and maybe get the injectors cleaned

drive another vehicle if possible
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Old 02-11-2013, 02:53 AM   #3
Jkmaynard
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I am going to guess that many misfires most likely won't be a ringland most of the time that is a single misfire highly unlikely 2 diff pistons would lose the rings at the same time could be fouled plugs ..

I would check plugs double check maf check turbo inlet pipe and pull the fuel filter and get a new one not sure if the sti has the filter under the hood but i know for sure there is one in the gas tank...
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Old 02-11-2013, 03:11 AM   #4
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Originally Posted by Uncle Scotty View Post
you very likely have crap in the tank that has fouled the fuel filter...and possibly fouled the injectors

do NOT beat on the car until you get this figured out as that may KILL IT when all you now need is a new filter and maybe get the injectors cleaned

drive another vehicle if possible
++++1
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Old 02-11-2013, 08:22 AM   #5
Zondacl2
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Thanks for the response guys, rhats what i was leaning towards fuel filter and plugs first, scotty trying to drive another car but have to chance it with the subie 3 times of the week cuz wifey uses the other car, not the best thing but i need to fix this asap, i know its only doing more damage in the long run,
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Old 02-11-2013, 08:34 AM   #6
Zondacl2
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Oh yea Jkmaynard the fuel filter is in the tank, for what reason i have no idea which engineer said to relocate it there but went to dealer they said they only sell the whole assembly which i think is stupid cuz its like $700, im going do some research and see if anyone has a part number to one from after market. I see rock auto has them for $40 for WRX i dont think for STI would be that much more $$ if its different. Thanks again
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Old 02-11-2013, 11:27 AM   #7
Jkmaynard
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They are full of crap i got my fuel filter from the dealer for 69.99 i have a 06 wrx not sure if they are the same part #
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Old 02-11-2013, 10:00 PM   #8
Uncle Scotty
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Originally Posted by Zondacl2 View Post
Oh yea Jkmaynard the fuel filter is in the tank, for what reason i have no idea which engineer said to relocate it there but went to dealer they said they only sell the whole assembly which i think is stupid cuz its like $700, im going do some research and see if anyone has a part number to one from after market. I see rock auto has them for $40 for WRX i dont think for STI would be that much more $$ if its different. Thanks again

order it online......jesus....the damed dealer parts departments are whack

i gotta change mine here when i get a chance
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Old 02-12-2013, 12:54 AM   #9
Zondacl2
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I agree with you there uncle scotty. They never have any parts for the sti anyways. I always end up having to go back to pick up a part i ordered.
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Old 03-02-2013, 12:35 PM   #10
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I'm having the exact same problem with my Forester, just started a couple days ago. Below 8 psi, perfectly normal, above 8 psi, heavy misfire. It's not rpm dependent at all (does not vary with air/fuel flow rate), 3k-6k rpm, no change. Mods/tune, the car has been unchanged for over a year. It's like something broke that controls high boost operation and only high boost operation. It's dead on consistent cold to hot and low rpm to high rpm and only will throw misfire codes.

So...what sensor only affects high boost?

Last edited by Back Road Runner; 03-02-2013 at 12:43 PM.
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Old 03-03-2013, 01:18 AM   #11
Uncle Scotty
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Originally Posted by Back Road Runner View Post
I'm having the exact same problem with my Forester, just started a couple days ago. Below 8 psi, perfectly normal, above 8 psi, heavy misfire. It's not rpm dependent at all (does not vary with air/fuel flow rate), 3k-6k rpm, no change. Mods/tune, the car has been unchanged for over a year. It's like something broke that controls high boost operation and only high boost operation. It's dead on consistent cold to hot and low rpm to high rpm and only will throw misfire codes.

So...what sensor only affects high boost?
bad plugs....bad coilpacks

coilpacks heat up..resistance increases, spark goes to ****
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Old 03-03-2013, 01:45 AM   #12
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But it drives great under 8psi, perfect in fact. Dead cold or fully heated, it drives exactly the same. It will drive perfectly fine up to 8psi at any rpm. I can give the car gas, build up 8psi at 2.5k rpm and run it all the way up to redline without any fuss. Then I can do the same but try for 12psi, and it will mis and mis all the way up. Really, it acts more like knock detection than misfire, but all it's throwing is misfire codes. The only "switch" to the effect is boost amount. The effect is constant, repeatable, and unchanging. The misfire codes are also on multiple cylinders, and the car does not misfire at all under 8psi in any condition.

There was no build up to the event, so it's apparently something failed in some way. It just started all of a sudden on my drive home from work a couple days ago. Bad plugs causes misses all the time. Bad coils effectively drop cylinders. It should be like disconnecting one. It would produce a noticeable drop in power, especially off boost. I know it's not the air/fuel sensor because it's not affected by open/closed loop changes. It's not air flow dependent nor fuel flow dependent because it doesn't change at all with rpm. I will produce identical results at less than half the flow rate of air or fuel through the system. I would also expect lean or rich codes too if this was the case. It shouldn't be the MAF sensor. If that was bad, the car pretty much wouldn't run worth crap. It would barely idle or get throttle.

In the end, there is something that functions at higher boost levels but does nothing at lower boost levels. All I've found so far is that it could possibly be a MAP sensor. Although I am not certain of this yet, it seems my XT has both a MAF and a MAP sensor and the MAP, according to other threads is there more specifically for boosted operation. This is pretty much the only thing I've managed to come across so far that might fit the issue, although there is no MAP code. Then again, operation may have to be quite bad to actually generate a code. My NA with a bad air/fuel sensor was pretty much undriveable before it threw a CEL. By undriveable I mean it couldn't idle by itself without at least 1/3 throttle, and the only way to drive it was heavy throttle=>coast=>heavy throttle=>coast otherwise it would buck like crazy. Even then it still took a lot of miles to get it to generate a CEL for it. It's hard to say how bad the MAP would have to be to generate a CEL code.
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Old 03-03-2013, 01:48 AM   #13
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sweetums......sugard000dle.....

listen to yer uncle heeeer.......LISTEN......check the coilpacks...LOOK at them...do they LOOK 'bloated' or mal shaped in any way?
do the SMELL burnt???
swap them and put some fresh plugs in and call me in the morning
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Old 03-28-2013, 12:24 AM   #14
Zondacl2
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You was right Uncle Scotty!! Fouled plugs and two bad coil packs. Shes up and running strong :-) thanks.
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Old 03-28-2013, 09:53 PM   #15
jmp6889928
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Definitely coilpacks. They go bad in the wink of an eye. Had the same problem on my 05 LGT and they even checked OK with DVOM off the car. I ALWAYS now keep a new one in the trunk because you never know when the damn things are going to just pop. When that happens, it usually lunches the plug too.
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Old 04-06-2013, 01:59 PM   #16
Back Road Runner
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Yeah, I'm at the same place. From any research I could find it's specifically a spark issue. I'm not sure if the ECU does anything specific in relation to boost, but most label it as spark blow out due to weak spark. I'm not sure what specifically creates weak spark versus intermittent, versus complete failure.

I first swapped coil packs between 3 and 1 to test if the code followed the pack. Boost went from 8-12 to about 2-5 psi, but I still got the code following cylinder 3. I pulled the spark plug and found the gap to be fine. However, the casing was cracked. I replaced the plug with a new one to test, and I was back up to around 10psi again but still a misfire. This time it did give me a cylinder 1 code, following the coil pack like I would expect. I have one on order to see if all ends well. I can't say if the plug messed up the coil pack or the coil pack messed up the plug. So now I will be tossing in a new coil pack and all new plugs (getting to be about that time anyways). Hopefully all ends well, will find out in about a week.
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