hadvw Posted October 19, 2016 Share Posted October 19, 2016 So.. Started getting temporary CELs (i.e. ones that go off after a few seconds) after a new tune from my tuner. No permanent CELs. Overall, the "really bad" period is shorter now. I noticed he changed the highest MAF g/s from 60 to 45. Seems to be missing a lot at 3600 rpm, and not many other places. (see LV) -ve fuel correction = too much fuel (losing air)? Another oddity: saw on BtSSM today where it records max/min values, that max boost target was 17.x, max actual boost 11.0. But, it seemed to be just really quickly - my Dig20Boost (hooked in after the BPV) still shows up to 20+ psi. But, again, it locked up after hitting even partial full-throttle, and much more gently. Also saw cyl #3 misfire hitting 14 - that's the highest I've seen. No other misfires (today). I feel it's down to injectors or coilpacks/wiring (at least until those are ruled out). My question: non-oem coilpacks are going for $80-90 for FOUR on ebay. I know that OEM parts are best, but.. How likely is it that these will be horrible? I'm thinking, they gotta be better than almost 12-year-old packs, right? OEM remanufactured are $45 on ebay, new OEM around $70. Trying to decide whether to go with: -compression/leak-down test right off the bat, and if nothing found, new plugs and/or new coils? Time is a factor right now.. And hey, while doing the test/plugs, $100 for new coils and the labor is pretty much free, since they already have to remove the old coils.. -slow and steady - swap coil 1 < - > 3, watch for misfire to move or not move, swap injectors, etc.. Right now, $200-300 isn't a big deal if it solves the issue. Plus, it's probably been 2-3 years since I did plugs the last time.. Link to comment Share on other sites More sharing options...
xt2005bonbon Posted October 19, 2016 Share Posted October 19, 2016 -slow and steady - swap coil 1 < - > 3, watch for misfire to move or not move, swap injectors, etc.. I would do this first. It is really quick to do and can be checked right away. Link to comment Share on other sites More sharing options...
StkmltS Posted October 19, 2016 Author Share Posted October 19, 2016 Definitely start with swapping the coil packs, spark plugs, and injectors (one at a time). What did you mean by "...it locked up after hitting even partial full-throttle, and much more gently."? My DiySB rebuild Got Misfires? Link to comment Share on other sites More sharing options...
hadvw Posted October 19, 2016 Share Posted October 19, 2016 Definitely start with swapping the coil packs, spark plugs, and injectors (one at a time). I'm going to do coil packs first. I may get someone to swap injectors (I don't like playing with fuel related stuff, but maybe it's time to learn). If it gets to "swap plugs", I'm putting new plugs in.. No messing around with that. What did you mean by "...it locked up after hitting even partial full-throttle, and much more gently."? Btssm. Before, when I hit WOT after accelerating onto the freeway, Btssm locked up (stopped getting data) 4 times out of 5. Today, I was more gentle, didn't go for the "floor it, huge surge", but more "gently increase throttle", and it still locked up. Time to go back to RR to see if it also locks up.. Or see if I can get a refund and move Btssm to my Galaxy S6, although that would only be temporarily.. Link to comment Share on other sites More sharing options...
StkmltS Posted October 20, 2016 Author Share Posted October 20, 2016 As long as you're using the same Google account you can download and use BtSsm on multiple devices. I have it on two phones and a tablet, and I only bought it once. Sent from inner space. My DiySB rebuild Got Misfires? Link to comment Share on other sites More sharing options...
xt2005bonbon Posted October 20, 2016 Share Posted October 20, 2016 ^ Link to comment Share on other sites More sharing options...
hadvw Posted October 21, 2016 Share Posted October 21, 2016 Ok, so swapped coil packs (1/3) today. Of course, somehow the cable fell off the #3 coil pack, so when I started it up, cyl #3 misfire instantly kept going up.. Tested twice, just to be sure, but it ran up to 80+ both times. After fixing the cable and re-starting, cyl #1 had a couple of misfires, so I'm thinking it IS the coil, but I'm going to go through a cold start tomorrow just to be sure. Interestingly, the 2 coil packs had different labels on them.. My wife didn't realize my cell phone isn't like hers, and pushing the middle of the screen doesn't take the picture. So, no pictures. By memory, the one from cyl #3 (the one under suspicion) had the label "STI" on it, and what looked like a Subaru part #. The one from cyl #1 had totally different markings on it. Something starting with F, but I can't for the life of me remember the exact name. Writing was also rotated 90 degrees, and the part number did not look like a Subaru part. I don't specifically remember replacing any coils, but it's possible it was done at some point to fix a similar issue or something. In any case, aftermarket seems to work, OEM (I'm guessing the "STI" one is OEM) seems to be failing. So, if misfire moves to cyl #1, time to buy at least one new coil. Link to comment Share on other sites More sharing options...
xt2005bonbon Posted October 21, 2016 Share Posted October 21, 2016 Nice progress. Keep us posted. The OEM coil markings should look like this one: http://www.celticmotorsport.com/catalog/images/22433AA640-3.JPG Link to comment Share on other sites More sharing options...
hadvw Posted October 21, 2016 Share Posted October 21, 2016 Yeah, I think that's the one. No misfires today.. Link to comment Share on other sites More sharing options...
hadvw Posted October 23, 2016 Share Posted October 23, 2016 Immediately after start today, saw 1 misfire on cyl #3, but then 5 minutes later, 45 misfires on cyl #1. So, it appears to have followed the non-OEM coil. Just ordered a new OEM coil. Debated about doing plugs as well... Holding off for now.. Link to comment Share on other sites More sharing options...
xt2005bonbon Posted October 23, 2016 Share Posted October 23, 2016 I'd say you can disregard the 1 count right after start up. This is somewhat pretty common. At least I do see that from that to time with both of my cars. Link to comment Share on other sites More sharing options...
148am Posted October 25, 2016 Share Posted October 25, 2016 I've read through and have been following this thread, as my recently acquired 05 XT has a no-code misfire on cyl 1 that I've been whittling away at as time allows. Great info in here and thanks to @StkmltS for letting the scope expand a bit along the way. Thanks to @heiche for BtSSM related hardware help. I learned about BtSSM through this thread and got it up and running last week. Excellent program. Link to comment Share on other sites More sharing options...
148am Posted October 26, 2016 Share Posted October 26, 2016 In skimming back through this thread, I didn't find anyone else's log showing timing (but I probably skimmed right over some, sorry about that). I wonder if anyone who has looked at these things can say if the logged timing data I'm seeing is typical. Looks like odd behavior to my untrained eyes. The log below is with the car at ~190°F, stationary and in neutral (manual trans). Idle is lumpy but steady at 750 RPM, then starts misfiring more sharply when I bring the revs up slightly. Timing is bouncing around during the former, then sets dead even during the latter. What gives? I'm lining up for some more diagnosis this weekend: swap coil packs, check plugs, compression test, test crank position sensor, check for vac leaks. I'll likely run a can of seafoam through the manifold for good measure. Link to comment Share on other sites More sharing options...
hadvw Posted October 28, 2016 Share Posted October 28, 2016 Quick update: got the coil pack Wednesday night (a bit of a surprise, didn't expect it until Friday from the shipping estimate). Installed Thursday AFTER the morning drive. A quick test drive, no problems. Another drive this morning (in warmish rain) and no issues. 1 misfire in cyl 4 at start, 1 in cyl 1 (the one with the new coil) somewhere in there. That's it. Doesn't mean it's solved, but at least it's showing signs of improvement. Getting this car to run again without worrying about this would be great. Link to comment Share on other sites More sharing options...
heiche Posted October 28, 2016 Share Posted October 28, 2016 Sounds to me like you got it! BtSsm - Android app/Bluetooth adapter. LV, logging, gauges and more. For 05-14 Legacy (GT, 2.5, 3.0, 3.6), 02-14 WRX, 04-14 STi, 04-14 FXT, 05-09 OBXT Link to comment Share on other sites More sharing options...
hadvw Posted October 31, 2016 Share Posted October 31, 2016 After 3 days in a row of no real issues, yeah, I'm 95% confident I got it.. Now to deal with the front-end clunking... Link to comment Share on other sites More sharing options...
xt2005bonbon Posted October 31, 2016 Share Posted October 31, 2016 Good. Front end clunking may be your control arm bushings being torn. I have to change mine as well. Link to comment Share on other sites More sharing options...
hadvw Posted October 31, 2016 Share Posted October 31, 2016 Good. Front end clunking may be your control arm bushings being torn. I have to change mine as well. Yeah, probably. Although I did Whiteline LCAs about 50k miles ago. May also be ball joints. We have some horribly bumpy roads around here.. Link to comment Share on other sites More sharing options...
xt2005bonbon Posted October 31, 2016 Share Posted October 31, 2016 True. I doubt the whiteline bushings would be torn though. They're pretty tough. Link to comment Share on other sites More sharing options...
hadvw Posted October 31, 2016 Share Posted October 31, 2016 True. I doubt the whiteline bushings would be torn though. They're pretty tough. I had someone else do them - am I supposed to see them separate into multiple pieces when jacking up the car? Looks like a top/bottom and middle section.. (this was while replacing sway bar bushings) Link to comment Share on other sites More sharing options...
StkmltS Posted October 31, 2016 Author Share Posted October 31, 2016 (edited) So either I missed it somehow, or it's a recent development, but my motor doesn't miss when it's cold. To be more specific, from a cold start, with zero driver throttle input, the car idles (almost) completely misfire-free until coolant temp reaches around 114°F. I recorded a log this morning of the car warming up, and there's a pretty obvious point where something changes and the (increasing) misses begin. There are a couple of seemingly random (single) misses early on in the log, but something obviously changes at TIME=123744 and the increasing misses begin happening. It'll take me quite a long time to sort through all of the data is this log to try to identify everything that changed, but the answer has to be in there somewhere. Well, at least I really want the answer to be in there somewhere. My hope is to dig as deep as possible into this log and identify everything that changes when/right before the misses start, and then identify and test the sensors associated with each parameter that changed. It's been brought up many times that I should investigate the wiring between the ECU and plugs/injectors. At this point I don't think it's worth my time looking for a wiring issue there. Here's why: if there was a problem (wiring/dirt/loose connection/etc) with my plugs/injectors, then vehicle speed wouldn't affect the misses every time. I've not-quite-proven that the misses do in fact change with vehicle speed every time, so I believe there is something (a failing sensor?) instructing the cylinder(s) to misfire under certain conditions that I haven't been able to fully identify. Somehow, somewhere, I think something is always feeding bad info into the ECU, and it only shows up at SPEED=0 because of the complicated relationship between all of the tables in the ROM. I'm frustrated, yet encouraged. Time to start a new spreadsheet listing factors that sometimes/always/never affect misfires. Until now this thread has been my sole method of keeping track of what's going on. The raw log is attached just in case anyone is curious.BtSsm_20161031_055841_ColdStartAndIdle.csv Edited October 31, 2016 by StkmltS My DiySB rebuild Got Misfires? Link to comment Share on other sites More sharing options...
xt2005bonbon Posted October 31, 2016 Share Posted October 31, 2016 So either I missed it somehow, or it's a recent development, but my motor doesn't miss when it's cold. To be more specific, from a cold start, with zero driver throttle input, the car idles (almost) completely misfire-free until coolant temp reaches around 114°F. That's about what I was experiencing as well with the 06. It never really misfires right at cold start and idle. I had to drive it just a bit. And then, when I got to THAT traffic light with the car not fully warmed up yet, misfire count was showing up at idle. Even with the engine fixed now, every time I get to THAT traffic light, I am always scared of misfires . Link to comment Share on other sites More sharing options...
Rhitter Posted October 31, 2016 Share Posted October 31, 2016 I had someone else do them - am I supposed to see them separate into multiple pieces when jacking up the car? Looks like a top/bottom and middle section.. (this was while replacing sway bar bushings) Yes, that's pretty normal. Check your swaybar endlinks, even when I think there is no way that could be the cause, it always is. In other news, I get misfires in two conditions 1. cold startup (I will get 1-2 across some random cylinders) 2. On shifting, clutch in misfire will appear (briefly). 1. Almost seems like intake manifold gaskets, but it's not that cold (55 degrees) and I can see orange tabs 2. Seems like Vacuum issue (which i think is supported by my LV) My OBXT build Link to comment Share on other sites More sharing options...
xt2005bonbon Posted October 31, 2016 Share Posted October 31, 2016 I should also add that I thought misfires were not showing up because the rpm was a bit too high at cold start idle. An interesting experiment would be to record the idle rpm you get at cold start; and then when you reach a lukewarm coolant temp and misfires are present, raise the rpm to the cold start idle rpm level, and see if the misfires persist. I'd be curious to hear the outcome. Link to comment Share on other sites More sharing options...
StkmltS Posted October 31, 2016 Author Share Posted October 31, 2016 I should also add that I thought misfires were not showing up because the rpm was a bit too high at cold start idle. An interesting experiment would be to record the idle rpm you get at cold start; and then when you reach a lukewarm coolant temp and misfires are present, raise the rpm to the cold start idle rpm level, and see if the misfires persist. I'd be curious to hear the outcome. I've done that. If it's missing and I raise the RPM it speeds up the misses, it doesn't reduce them. The only time I've seen RPM affect the misses was a few days ago when I posted a chart of me repeatedly tapping on the throttle for 10-20 seconds. That's another reason I think the ECU is being fed incorrect information from somewhere. It's like there's a "misfire table" deep in the ROM and for whatever reason my ECU is going to that table when the right conditions are met. I know that's rediculous, but that's almost what's happening. The more I learn about tuning, the more I think it's a sensor issue. Sent from inner space. My DiySB rebuild Got Misfires? Link to comment Share on other sites More sharing options...
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