JmP6889928 Posted June 15, 2013 Share Posted June 15, 2013 I have been having a cylinder 2, and 4 misfire. Idle is ROCK solid with it plugged in and with it unplugged. The misfire only happens under a load. With MAF disconnected I can run and drive at any throttle without misfire. Any ideas? Ok....now wait a minute. You said that you've been having the misfire and did this happen all of a sudden? How can any of the vacuum lines be hooked up incorrectly unless you did them yourself? Have you messed with the lines trying to fix it and don't know if you put them in the correct spot or did you have someone else do it for you? If it just started having misfires out of the blue, then there is a mechanical/electrical issue of some kind that something has failed in. Fuel, timing, spark, air, are what makes it run. If there is no CEL or you haven't done anything yourself to it, then there is something that failed. Last I checked, unless there is some elf sh*t in your garage and they were running around at night messing with you, vacuum lines don't just re-route themselves. Simple logic. Link to comment Share on other sites More sharing options...
teamafx Posted June 15, 2013 Author Share Posted June 15, 2013 misfire was happening prior to engine work, had horrible misfire at idle, found broken ringlands and the engine was sent out, honed, and reassmbled with new internals. Now no misfire at idle, but misfire under load has been happening since the engine was reassembled. I did the work myself and have triple checked everything, I can only assume something got misrouted and Im not seeing it. Idle is rock solid, no sign of vac leaks and it throws the misfire with the air filter in there and is almost undriveable, pull the air filter out and you can run and drive with no check engine light for misfire. Link to comment Share on other sites More sharing options...
mwiener2 Posted June 15, 2013 Share Posted June 15, 2013 You have a major air leak My Mods List (Updated 8/22/17) 2005 Outback FMT Running on Electrons Link to comment Share on other sites More sharing options...
teamafx Posted June 15, 2013 Author Share Posted June 15, 2013 I removed the vac hose from intake to rear and smoked it again, I can pull any individual hose and it will smoke from that spot. I can pull the air inlet and it will smoke from that spot. NO LEAKS! That is not the issue Link to comment Share on other sites More sharing options...
JmP6889928 Posted June 15, 2013 Share Posted June 15, 2013 Plugged or broken catalytic converter. Link to comment Share on other sites More sharing options...
teamafx Posted June 15, 2013 Author Share Posted June 15, 2013 seems to have good exhaust flow, but that is a possibility Link to comment Share on other sites More sharing options...
teamafx Posted June 15, 2013 Author Share Posted June 15, 2013 Converter wouldnt causd just that bank to go wacky Link to comment Share on other sites More sharing options...
apexi Posted June 15, 2013 Share Posted June 15, 2013 Have you checked to see if the timing belt is off a tooth or 2 yet? Worth a try Link to comment Share on other sites More sharing options...
mwiener2 Posted June 16, 2013 Share Posted June 16, 2013 Are you filling and pressurizing the entire intake tract or just the evap system? The symptoms you describe and the ways things get affected when you play with them all point to an air leak. Find it. The previous motor blew up... probably from an undiagnosed air leak. FIND IT!!! My Mods List (Updated 8/22/17) 2005 Outback FMT Running on Electrons Link to comment Share on other sites More sharing options...
teamafx Posted June 16, 2013 Author Share Posted June 16, 2013 Are you filling and pressurizing the entire intake tract or just the evap system? The symptoms you describe and the ways things get affected when you play with them all point to an air leak. Find it. The previous motor blew up... probably from an undiagnosed air leak. FIND IT!!! I have pressurized the entire system with compressed air and not found a leak. the entire intake system was pressurized and no air leaks. Link to comment Share on other sites More sharing options...
mwiener2 Posted June 16, 2013 Share Posted June 16, 2013 then you're not telling us something or you're doing it worng My Mods List (Updated 8/22/17) 2005 Outback FMT Running on Electrons Link to comment Share on other sites More sharing options...
teamafx Posted June 16, 2013 Author Share Posted June 16, 2013 Pressurizing the system is easy, so no Im not doing it wrong. Working with a buddy who is a master subaru tech and he is leaning towards an issue with the tgv. Link to comment Share on other sites More sharing options...
mwiener2 Posted June 16, 2013 Share Posted June 16, 2013 A "master tech" is still a line tech. Thanks for the name drop. I'd be surprised if it was the TGV based on your description of the problems. My Mods List (Updated 8/22/17) 2005 Outback FMT Running on Electrons Link to comment Share on other sites More sharing options...
teamafx Posted June 16, 2013 Author Share Posted June 16, 2013 Wow....not going to get into that comment......anyone else? Link to comment Share on other sites More sharing options...
mwiener2 Posted June 16, 2013 Share Posted June 16, 2013 wow, you've come to the internet to fix a problem and you're not getting the answers you wanted. No one has anything else because the ideas have been exhausted based on the information given. Figure out what information you haven't told us (it has a tune? misfiring rich or lean?) or what you are doing wrong in your diagnosis. My Mods List (Updated 8/22/17) 2005 Outback FMT Running on Electrons Link to comment Share on other sites More sharing options...
teamafx Posted June 16, 2013 Author Share Posted June 16, 2013 wow, you've come to the internet to fix a problem and you're not getting the answers you wanted. No one has anything else because the ideas have been exhausted based on the information given. Figure out what information you haven't told us (it has a tune? misfiring rich or lean?) or what you are doing wrong in your diagnosis. no tune, nothing I havent told you...Your air leak answer isnt correct.....others have pm'd me different ideas as well which I am fully researching. I appreciate the help but at this point your input isnt really helping either so feel free to not post. Of course the ideas have been exhausted as this is why Im on here, none of it makes sense. This was a new to me car and Im unaware of any previous history that may or may not have caused my issue so I am came here to ask for ideas to try and look beyond what i see as I am too close to it everyday and may be missing something (not an air leak). BTW the "line tech" is a master subaru, mercedes, bmw, and audi tech. ASE master with L1, and is honestly the best tech I have ever been around and I have been a professional in the business for 18 years. He hasnt seen the car in person as time has not permitted and I was trying to not have to get him involved. Link to comment Share on other sites More sharing options...
apexi Posted June 17, 2013 Share Posted June 17, 2013 Can we go over again what you've tried? What are the exact symptoms once again? Currently just a misfire in cylinders 2 and 4 under load? You say that when you remove the new, clean oem air filter from the air box the misfire goes away? When you disconnect the maf harness, that also causes the misfires to go away? I don't know much about the TGV, but from what I do understand this doesn't sound like that's the problem, but anything is possible. -Did you verify that the timing is correct. -Are you 100% positive that the 2004 outback xt injectors are good? Try swapping cylinder 2 and 4 injectors with cylinder 1 and 3 injectors. -Have you inspected the injector wiring harnesses? -Are you 100% sure that the cylinder 2/4 coil packs are good? -If you are truly out of ideas, it wouldn't hurt to swap the driver side OCV with the passenger side OCV to see if the misfire moves. -Are the vacuum lines connected to the T under the intercooler all connected? -You mentioned changing the AF sensor, was this the front oxygen sensor or the rear oxygen sensor? I want to help you figure this out, but I'm still unsure of what has been 100% covered. Link to comment Share on other sites More sharing options...
SBT Posted June 17, 2013 Share Posted June 17, 2013 Presume you've already checked this (and I don't think you smoke/pressure test will show it), but I suspect one or more of your TGV-to-Cylinder Head gaskets are leaking under high-heat/boost pressure. These need to be installed and torqued carefully. And IIRC, Subaru has a replacement part number as well. - Pro amore Dei et patriam et populum - Link to comment Share on other sites More sharing options...
fahr_side Posted June 17, 2013 Share Posted June 17, 2013 SBT has a good point. Remember that disconnecting the MAF has the effect of putting the ECU into a kind of limp mode where it's using very conservative maps for timing and very rich maps for fuel. Fueling is done via the MAP sensor as a stop-gap measure... a rather crude speed-density fueling mode. If you're running somewhat lean, either because you have a leak or a clogged injector or or or, it's likely that limp mode will actually make it run better. Since you can read off the trouble codes, can you also see what your fuel trims are? It would be very helpful if you could take a learning view for us to see. Obligatory '[URL="http://legacygt.com/forums/showthread.php/2008-gh8-238668.html?t=238668"]build thread[/URL]' Increased capacity to 2.7 liters, still turbo, but no longer need spark plugs. Link to comment Share on other sites More sharing options...
mwiener2 Posted June 17, 2013 Share Posted June 17, 2013 If you ever blow a boost tube while on the road, you can go into "limp mode" and make it home to fix it. Good trick to know. I'm really impressed by someone that gets a title from passing a multiple choice test. ASE and the whole automotive certification process is a bit of a joke. It doesn't prove you know more about cars than the next guy. It proves you PAID to take a multiple choice test (maybe studied, it's not a hard test) and moved yourself into a higher pay bracket. It's name dropping, I'm not impressed. He's still a line tech. Those certifications don't mean anything unless you want a job as a line tech. BTW, a Subaru Master Tech built my motor. It's been one of the nicest motors I've ever come across, and I build motors. But I don't call him when I have diagnostic problems. My Mods List (Updated 8/22/17) 2005 Outback FMT Running on Electrons Link to comment Share on other sites More sharing options...
teamafx Posted June 18, 2013 Author Share Posted June 18, 2013 even if this had an air leak, why would it only cause a misfire on one bank Link to comment Share on other sites More sharing options...
fahr_side Posted June 18, 2013 Share Posted June 18, 2013 even if this had an air leak, why would it only cause a misfire on one bank If the TGV housing or it's gaskets leak you can find the symptoms limited to that bank. It happens. Obligatory '[URL="http://legacygt.com/forums/showthread.php/2008-gh8-238668.html?t=238668"]build thread[/URL]' Increased capacity to 2.7 liters, still turbo, but no longer need spark plugs. Link to comment Share on other sites More sharing options...
mwiener2 Posted June 18, 2013 Share Posted June 18, 2013 even if this had an air leak, why would it only cause a misfire on one bank What is the meaning of life? My Mods List (Updated 8/22/17) 2005 Outback FMT Running on Electrons Link to comment Share on other sites More sharing options...
Max Capacity Posted June 19, 2013 Share Posted June 19, 2013 What is the meaning of life? Hey I know the answer to that one. 42 OP I beginning to agree you may have a gasket bad at one of the TGV's to head. Check and make sure the 4 bolts are tight. on the passenger side. That's where 1 and 3 are. 305,600miles 5/2012 ej257 short block, 8/2011 installed VF52 turbo, @20.8psi, 280whp, 300ftlbs. (SOLD). CHECK your oil, these cars use it. Engine Build - Click Here Link to comment Share on other sites More sharing options...
fahr_side Posted June 21, 2013 Share Posted June 21, 2013 Update? Obligatory '[URL="http://legacygt.com/forums/showthread.php/2008-gh8-238668.html?t=238668"]build thread[/URL]' Increased capacity to 2.7 liters, still turbo, but no longer need spark plugs. Link to comment Share on other sites More sharing options...
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