StkmltS Posted January 15, 2017 Author Share Posted January 15, 2017 Lately I've been paying close attention to how the misses feel, and I think I finally know how to describe it. Do you know how the car feels when you're in that mid-2k RPM "stumble-stutter" zone? Well, if you could keep the car right in that zone so that it's continually stumble-stuttering, that's how my car feels when it's idling at 0 mph. I'm going to relocate the FPR ref line to the BPV and see if either condition improves. My DiySB rebuild Got Misfires? Link to comment Share on other sites More sharing options...
TheMonaLisa Posted January 16, 2017 Share Posted January 16, 2017 Last week my car started doing exactly what your car is doing. Cylinder 2, intermittent, everything sounds exactly the same as described in your first post. It has always idled rough on cold starts ever since I installed larger injectors but never got a CEL, stalling, ect until last week. My car has 140k miles. Link to comment Share on other sites More sharing options...
TheMonaLisa Posted January 23, 2017 Share Posted January 23, 2017 (edited) Ruled out a possible coilpack failure by switching the cylinder 2 coilpack with cylinder 4. Left to investigate is the spark plug and injector. Sent from my iPhone using Tapatalk Edited January 23, 2017 by TheMonaLisa Link to comment Share on other sites More sharing options...
StkmltS Posted January 23, 2017 Author Share Posted January 23, 2017 Good luck! I'll be interested to see what ends up fixing your problem. My DiySB rebuild Got Misfires? Link to comment Share on other sites More sharing options...
l88m22vette Posted January 27, 2017 Share Posted January 27, 2017 Same problem for me, P0302 (specific code) and a P0420 (background code). New coilpack, swapped injectors, no change. That said, this started to occur following a mild accident in December (~5mph), someone cut me off and I skidded on slush. The exhaust got a little louder and the stock manifold has a lot of rust so I'm going to check for an exhaust runner leak first, though I don't know if that'd cause the P0302. I don't want to just take it in and shell out tons of money since it could be a million things, but I also don't know where to start. Link to comment Share on other sites More sharing options...
StkmltS Posted January 27, 2017 Author Share Posted January 27, 2017 Same problem for me, P0302 (specific code) and a P0420 (background code). New coilpack, swapped injectors, no change. That said, this started to occur following a mild accident in December (~5mph), someone cut me off and I skidded on slush. The exhaust got a little louder and the stock manifold has a lot of rust so I'm going to check for an exhaust runner leak first, though I don't know if that'd cause the P0302. I don't want to just take it in and shell out tons of money since it could be a million things, but I also don't know where to start. Maybe your manifold is cracked. I'm not sure if an exhaust leak can cause misfires, but with it being that close to the motor I'd say that anything is fair game. I would definitely start looking there. You know of something that happened at the same time as the misfires starting, so it seems very reasonable to think that they're connected. Everything I've tried without success has caused me to rethink what I used to think wasn't reasonably possible. My DiySB rebuild Got Misfires? Link to comment Share on other sites More sharing options...
TheMonaLisa Posted January 29, 2017 Share Posted January 29, 2017 Last week my car started doing exactly what your car is doing. Cylinder 2, intermittent, everything sounds exactly the same as described in your first post. It has always idled rough on cold starts ever since I installed larger injectors but never got a CEL, stalling, ect until last week. My car has 140k miles. Swapped the spark plug, coil pack, and injector from cylinder 2 with another cylinder. The misfire stayed in cylinder 2. Going to make a boost leak tester tomorrow, maybe there is a leak in the intake manifold gasket... Link to comment Share on other sites More sharing options...
xt2005bonbon Posted January 29, 2017 Share Posted January 29, 2017 time for compression/leakdown test. Link to comment Share on other sites More sharing options...
TheMonaLisa Posted January 30, 2017 Share Posted January 30, 2017 time for compression/leakdown test. Did a compression test today. It was 40F outside and the engine was bone cold. Cylinder 1: 130 psi Cylinder 2: 120 psi Cylinder 3: 130 psi Cylinder 4: 120 psi After the compression test I proceeded to put in 4 new spark plugs, a new battery, injector cleaner, and Seafoam in the vac line. Nothing made a difference. I upped the idle rpm with my Accessport to +300 oven normal (~1,050 rpm). This resolved the misfire issue for now but it is a bandaid fix. Link to comment Share on other sites More sharing options...
LatentWagen Posted January 30, 2017 Share Posted January 30, 2017 Did a compression test today. It was 40F outside and the engine was bone cold. Cylinder 1: 130 psi Cylinder 2: 120 psi Cylinder 3: 130 psi Cylinder 4: 120 psi After the compression test I proceeded to put in 4 new spark plugs, a new battery, injector cleaner, and Seafoam in the vac line. Nothing made a difference. I upped the idle rpm with my Accessport to +300 oven normal (~1,050 rpm). This resolved the misfire issue for now but it is a bandaid fix. Did you swap around injectors, too? Hopefully it's a malfunctioning injector at idle... on the other end of the PITA spectrum, a poorly seated exhaust valve won't always show up on a compression test. LW's spec. B / YT / IG Link to comment Share on other sites More sharing options...
StkmltS Posted January 30, 2017 Author Share Posted January 30, 2017 Did a compression test today. It was 40F outside and the engine was bone cold. Cylinder 1: 130 psi Cylinder 2: 120 psi Cylinder 3: 130 psi Cylinder 4: 120 psi After the compression test I proceeded to put in 4 new spark plugs, a new battery, injector cleaner, and Seafoam in the vac line. Nothing made a difference. I upped the idle rpm with my Accessport to +300 oven normal (~1,050 rpm). This resolved the misfire issue for now but it is a bandaid fix. Regretfully, it sounds like I need to welcome you into the club. Ever seen a cat or dog chase it's tail? It's kinda like that. I had a similar bandaid for quite a while. It sticks pretty good so don't feel too bad. Close your eyes, pretend the problem is gone, and try to move on with your life. I'd be happy with those compression numbers. Next you should do a leak-down test. Do you have a wideband o2? Monitoring your AFR could help you figure out if it's a fuel or spark problem. Your AP may not give you the ability to change the target AFR, but I saw good results (less misses) by increasing the target AFR (increasing fuel) by changing the lowest (top left) 2 or 3 cells in the CL Fueling Target Compensation (Load) table to "-0.059" (they were "-0.441"). *disclaimer* Your results may vary. Side effects of modifying your tune may include: runny nose, bloated stomach, cramps, bleeding from the eardrums, bleeding from the anus, checking your poo to see if you're bleeding from the anus, vomiting, diarrhea, nausea, itchy eyelids, ringland failure paranoia, ringland failure obsession, ringland failure denial, actual ringland failure, ringworms, rebuilds, excessive loss of wallet-weight, and watery eyes. Early symptoms of DIY-everything syndrome have also been observed in extreme cases of road-tuning, eventually resulting in death (of you or the car, whichever comes first). My DiySB rebuild Got Misfires? Link to comment Share on other sites More sharing options...
xt2005bonbon Posted January 30, 2017 Share Posted January 30, 2017 Yeah. time for leak-down. But if it were me, I'd just go ahead and check the valve clearance. Pretty easy to do. Both of my cars suffered from a tight exhaust valve on #2. Caught it early enough so it was a relatively inexpensive fix (assuming you fix it yourself). Link to comment Share on other sites More sharing options...
StkmltS Posted January 30, 2017 Author Share Posted January 30, 2017 (edited) Yeah. time for leak-down. But if it were me, I'd just go ahead and check the valve clearance. Pretty easy to do. Both of my cars suffered from a tight exhaust valve on #2. Caught it early enough so it was a relatively inexpensive fix (assuming you fix it yourself). Yeah I bet, cause you've done your valves like 25 times by now :lol::lol: You should just put this in your signature: "Check your valve clearances, these cars need it!" *edit* you should upgrade to a paid membership so that you can have a signature for my nifty quote. Or maybe you haven't gotten enough use out of this forum? Edited January 30, 2017 by StkmltS My DiySB rebuild Got Misfires? Link to comment Share on other sites More sharing options...
xt2005bonbon Posted January 30, 2017 Share Posted January 30, 2017 Yeah I bet, cause you've done your valves like 25 times -23=2 by now :lol::lol: FTFY. You should just put this in your signature: "Check your valve clearances, these cars need it!" that's a real good one. Link to comment Share on other sites More sharing options...
xt2005bonbon Posted January 30, 2017 Share Posted January 30, 2017 Aaaaaand you still have not checked your spark plug in #2 btw Link to comment Share on other sites More sharing options...
ktm200 Posted January 30, 2017 Share Posted January 30, 2017 Did a compression test today. It was 40F outside and the engine was bone cold. Cylinder 1: 130 psi Cylinder 2: 120 psi Cylinder 3: 130 psi Cylinder 4: 120 psi After the compression test I proceeded to put in 4 new spark plugs, a new battery, injector cleaner, and Seafoam in the vac line. Nothing made a difference. I upped the idle rpm with my Accessport to +300 oven normal (~1,050 rpm). This resolved the misfire issue for now but it is a bandaid fix. I did the exact same thing. Started back late last winter. Rare misfire code when it was really cold out and I first started the car. If I cleared the code when it was warm, it wouldn't come back for the day. And it was only a couple times a month. Then summer rolled around and it rarely came up again. Until this winter, started to get worse. Raising the RPM worked for a bit, until it started running terribly and was misfiring at idle regardless of engine temps and when lifting off the throttle for braking. Compression tests were all fine. 130-135psi cold on all cylinders. However, when we tried pressurizing the cylinders for a leakdown, cylinder 4 (the one misfiring) wouldn't hold anything. Pulled the head, shined a light down the exhaust port, could see light all the way around one of the exhaust valves. I know its been said before, but a good compression test really might not tell the whole story. Link to comment Share on other sites More sharing options...
StkmltS Posted January 30, 2017 Author Share Posted January 30, 2017 (edited) Aaaaaand you still have not checked your spark plug in #2 btw But, but, but, it's still cold outside. I'm pretty sure my problem could possibly might have a chance of being partially fueling related. If that doesn't instill a reader with confidence I don't know what will. In post #676 (top of previous page) I described how my misses feel. Weeeeeeeeeel as it turns out, I am now able to cause the misses to appear while driving if I turn on cruse control on a flat stretch of highway and get those RPMs right in that sweet little stumble/stutter zone. On my car that sweet zone is right around 2.5-2.7k. I don't know if the problem has worsened, or maybe it's always been like this and I didn't pay it any attention because I thought it was just the irritating stumble/stutter issue that other people have been fighting for centuries. Either way, I think whatever is causing that may be correlated with my misfires. Maybe I have a pinhole leak in one of my fuel lines. I bought a bottle of fuel system UV dye and I'm going to try it out when this tank of gas is about gone. Hopefully I can get my garage cleaned out (enough) by then. Edited January 31, 2017 by StkmltS My DiySB rebuild Got Misfires? Link to comment Share on other sites More sharing options...
birkhoff Posted January 30, 2017 Share Posted January 30, 2017 I'm with bonbon on this one. Check your valve clearances. This isn't a fun job, and if you do find a problem, it's even worse to do anything about it, but for both these reasons it seems a too many of these cars don't get the attention they should in the valve dept. Marginally tight exhaust valves may not show on cold compression. The valves need to heat up. Hot compression test is not really an option, or at any rate, not for the faint of heart. Same problem with a leak down test on a cold engine. After following this issue for some time, I'm starting to think a significant number of these engines are torn down for suspected ring problems, when in fact it is the top end and valves that are to blame. Mine, for example. Link to comment Share on other sites More sharing options...
xt2005bonbon Posted January 30, 2017 Share Posted January 30, 2017 After following this issue for some time, I'm starting to think a significant number of these engines are torn down for suspected ring problems, when in fact it is the top end and valves that are to blame. Mine, for example. Link to comment Share on other sites More sharing options...
TheMonaLisa Posted February 4, 2017 Share Posted February 4, 2017 (edited) Set a new personal record! Pegged out the cylinder 2 roughness monitor at 99 count. Adjusted the idol +300 rpm with the AP since the misfire is only at idol. That helped for a few days but the misfire has progressed to misfiring even with the raised idol. I did notice that it misfires much more frequently when the engine is cold vs operating temp. Talked with a Subaru dealer and they think there is a crack in something. I somewhat agree, especially since the compression check of cylinder 2 took slightly longer than the other cylinders to hit max pressure and the engine temperature affects the severity of the misfire. Edited February 4, 2017 by TheMonaLisa Link to comment Share on other sites More sharing options...
xt2005bonbon Posted February 4, 2017 Share Posted February 4, 2017 99 is the max the count will go to. If it misfired that much, it must be pretty bad. I would stop driving it and really figure out what is going on. Are you going to check your valve clearances to rule that one out? Link to comment Share on other sites More sharing options...
TheMonaLisa Posted February 4, 2017 Share Posted February 4, 2017 99 is the max the count will go to. If it misfired that much, it must be pretty bad. I would stop driving it and really figure out what is going on. Are you going to check your valve clearances to rule that one out? I had planned to check the valve clearances but the problem has gotten so bad so quickly that it can't just be valve clearance. The misfire could still be a valve problem but I would think it's more serious than an adjustment. I would stop driving it if I could (only car), but then again it drive perfect fine. Spent the day looking for an 07-09 Spec. B. Also put a call into IAG for a quota of a prebuilt engine. Link to comment Share on other sites More sharing options...
StkmltS Posted February 5, 2017 Author Share Posted February 5, 2017 Don't buy a motor yet! Do everything you can before you get that drastic. I'm speaking from experience... a new motor may not fix the problem. Sent from inner space. My DiySB rebuild Got Misfires? Link to comment Share on other sites More sharing options...
TheMonaLisa Posted February 5, 2017 Share Posted February 5, 2017 Don't buy a motor yet! Do everything you can before you get that drastic. I'm speaking from experience... a new motor may not fix the problem. Sent from inner space. The only thing left to do then is somehow test the engine electrical harness Link to comment Share on other sites More sharing options...
StkmltS Posted February 5, 2017 Author Share Posted February 5, 2017 I've thought "the only thing left is..." about 15 times. That's why now I only say "the next thing is..." Sent from inner space. My DiySB rebuild Got Misfires? Link to comment Share on other sites More sharing options...
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