xt2005bonbon Posted September 22, 2016 Share Posted September 22, 2016 also how did your empirical testing go last night? (wiggles and what-not) +1. Link to comment Share on other sites More sharing options...
StkmltS Posted September 22, 2016 Author Share Posted September 22, 2016 also how did your empirical testing go last night? (wiggles and what-not) I wiggled and shimmied and jimmied the clips, But nothing I played with could change those mean blips. I'll twist the little pins this weekend I'll try, If wifey does rest her all watching eye. My DiySB rebuild Got Misfires? Link to comment Share on other sites More sharing options...
StkmltS Posted September 22, 2016 Author Share Posted September 22, 2016 For giggles, if it's having another episode of misfiring at idle, can you unplug the driver-side OCV wiring connector? Just curious if misfiring stops (or starts) Just tried it, no change. My DiySB rebuild Got Misfires? Link to comment Share on other sites More sharing options...
hadvw Posted September 22, 2016 Share Posted September 22, 2016 Keeping a close eye on this. Ever since I upgraded injectors + turbo (bnr16g) 6 or 7 years ago and got tuned, around this time of year when it's colder in the mornings, I've had a stumble at idle for about 3-5 minutes. And specifically around 5-7 minutes after starting the car, just as it switches from "cold" (open loop?) to "warmed up" (closed loop?) mode. After it fully warms up, usually goes away. Was worst with the initial Cobb AP v1 tune. The newer open-source tune made it better. It was bad enough that it often stalled somewhere along the main street going towards the highway. My solution was to raise the idle rpm some, first using OpenSSM (had to re-do every time the ECU got reset), then editing the tune manually with RomRaider. Doing that mitigated the problem 90%. All was good for several years. Just had it happen again this week. P303/CEL, but that was the day AFTER it stalled at the light. Didn't stall with the CEL, but a noticeable shudder. No issues at WOT, and no issues with warmer temps, or when cold or fully warmed up. I just remembered I got an updated tune over the last year, and haven't updated the idle rpm yet, just the mpg multiplier.. Probably time to do that. Would love to actually diagnose it, though. Some moisture causing a partial short from the coils? Dirty injectors? I've had the DW650cc's in there for 60k+ miles now, bought used, never had 'em cleaned. I swapped plugs several times over the years, never saw anything unusual (as far as I could tell - I'm no expert). Guess I need to start logging in the mornings when driving the kiddos to school.. What parameters should I log? Link to comment Share on other sites More sharing options...
LatentWagen Posted September 23, 2016 Share Posted September 23, 2016 Why does it happen when the car stops, but not when the car is moving? It makes no sense and I bet whatever the cause is has something to do with speed. I need to find something connected to the engine that changes with vehicle speed (vs engine RPM). There are tuning parameters for this. I notice it because my idle is slightly higher when the car is moving (even if just idling out of gear while slightly rolling)... as soon as I stop all the way, idle settles to the lower ~750RPM range. LW's spec. B / YT / IG Link to comment Share on other sites More sharing options...
rhino6303 Posted September 23, 2016 Share Posted September 23, 2016 I looked in your other thread but couldn't find my answer. Did you delete the tgvs? If you did, it can create issues with cold engine idle and low rpm idle. Some have them and some don't. Link to comment Share on other sites More sharing options...
hadvw Posted September 23, 2016 Share Posted September 23, 2016 If you're asking me - still have stock TGVs. I also replaced AVCS valves over the summer.. Driver's side was easy, passenger side a PITA to get the old one out.. Link to comment Share on other sites More sharing options...
StkmltS Posted September 23, 2016 Author Share Posted September 23, 2016 I looked in your other thread but couldn't find my answer. Did you delete the tgvs? If you did, it can create issues with cold engine idle and low rpm idle. Some have them and some don't. Pre-rebuild I replaced the TGV-to-head gaskets hoping it would fix my problem. I was at my wits end and stabbing in the dark. While I had the IM off I gutted and ported the TGVs. I saw no change in misfires going from yes-TGVs to no-TGVs. My DiySB rebuild Got Misfires? Link to comment Share on other sites More sharing options...
heiche Posted September 23, 2016 Share Posted September 23, 2016 Do you have access to an oscilloscope? I suppose you could backprobe the wires right at the injector and coil to see which signal is lost when it throws a fit. Might narrow it down a bit. 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...
StkmltS Posted September 23, 2016 Author Share Posted September 23, 2016 Do you have access to an oscilloscope? I suppose you could backprobe the wires right at the injector and coil to see which signal is lost when it throws a fit. Might narrow it down a bit. Nope. My DiySB rebuild Got Misfires? Link to comment Share on other sites More sharing options...
Rhitter Posted September 26, 2016 Share Posted September 26, 2016 Wanna join my misfire club? I'm interested in seeing what ends up being the problem. Sent from inner space. From MTBs thread, just joining this one. I am a new member of this club. Car was running great, then I replaced GS DP with OEM for SMOG and someone after that I introduced more FKC and (FKLC sometimes) and random misfires (1-3 counts) across a variety of cylinders. I tried to tighten up the bolts and blowing into the BPV line to see if I could hear any leaks. And I looked at the TMIC throttle body hose, but it looks connected well. Nothing so far. I usually have a misfire on three show up before the others though, might order a new coilpack and see if that fixes it. It's possible they just got old (just happened to my 2007 honda fit with misfires / CEL across three cylinders) Is there a recommended brand for coilpacks for Subaru - or is buying OEM best? Because the counts are so low, I am not too concerned, but it's not something that was there before, so I would like to fix it. My OBXT build Link to comment Share on other sites More sharing options...
xt2005bonbon Posted September 26, 2016 Share Posted September 26, 2016 Under which conditions do the counts occur? Always the same cylinders? Engine temp dependent? What is the max count you've seen per cylinder? What are your long term fuel trims? Link to comment Share on other sites More sharing options...
xt2005bonbon Posted September 26, 2016 Share Posted September 26, 2016 And hold on before 'wasting' money in getting new coilpacks. OEM runs like 70-80$ a piece. I also think OEM is best. Link to comment Share on other sites More sharing options...
Rhitter Posted September 26, 2016 Share Posted September 26, 2016 (edited) Under which conditions do the counts occur? Always the same cylinders? Engine temp dependent? What is the max count you've seen per cylinder? What are your long term fuel trims? Under which conditions do the counts occur? All conditions. Slightly worse cold (I have the orange tabs on my TGVs), but happens at temp to. Flooring / not flooring / idle / steady state doesn't seem to impact it Always the same cylinders? No, need to monitor more, but it happens across all 4. I think 3 is the most frequent What is the max count you've seen per cylinder? 3. Usually only 1, which quickly becomes 0 What are your long term fuel trims? How do I check this with BtSsm? Edited September 26, 2016 by Rhitter My OBXT build Link to comment Share on other sites More sharing options...
xt2005bonbon Posted September 26, 2016 Share Posted September 26, 2016 What is the max count you've seen per cylinder? 3. Usually only 1, which quickly becomes 0 ^Do these counts pop up once in a while, kinna like random or do they consistently show up? Personally, I would not worry much about such low counts though. You begin to worry when you see 10+, or 32+. From my personal experience, a CEL will show up if the count goes like 30+ a couple of times in a given cylinder. What are your long term fuel trims? How do I check this with BtSsm? Just pull an LV and the four values will show up there. Post it up here. You could also see these live at all times (as I do) but you'd need heiche's help to set these four custom fields up. Pretty easy though. Link to comment Share on other sites More sharing options...
Rhitter Posted September 27, 2016 Share Posted September 27, 2016 After a 10 minute drive http://i.imgur.com/sGcFQX7.png My OBXT build Link to comment Share on other sites More sharing options...
StkmltS Posted September 27, 2016 Author Share Posted September 27, 2016 (edited) Your LV shows that your computer is adding 5.2% more fuel in the "B" airflow range. Usually about +/- 5% is generally accepted as healthy, so you're probably ok as-is. The ECU adding fuel means that the car is seeing evidence that "extra" air is getting into the motor that the MAF sensor isn't seeing (un-metered air). So basically you may have a small vacuum leak somewhere. Random spikes in your AFR, maybe caused by a vacuum leak, could cause misfires... I think? Swap coil pack #3 with coil pack #1 and see if most of your misfires move to cylinder #1. If the misses move, then your problem is the coil. If the misses don't change, then you have to dig deeper for a vacuum leak. Tip: use a sharpie and write "3" on the coil pack that's currently in cylinder 3. Just a little clarification for anyone confused: Vacuum leak = un-metered air leaks IN under vacuum = ECU adds fuel = positive LV. Boost leak = air leaks OUT under boost = ECU takes away fuel = negative LV. Edited September 27, 2016 by StkmltS My DiySB rebuild Got Misfires? Link to comment Share on other sites More sharing options...
xt2005bonbon Posted September 27, 2016 Share Posted September 27, 2016 that does not look too bad really. As you may know, we usually want these numbers within +/-5%. Keep an eye on them by pulling lv on a regular basis. These numbers can change pretty fast btw depending on your driving conditions of course. Still have this question: "Do these counts pop up once in a while, kinna like random or do they consistently show up." Link to comment Share on other sites More sharing options...
StkmltS Posted September 27, 2016 Author Share Posted September 27, 2016 Something really, really funky has been going on for a couple of days. At first I thought it had something to do with a change I made in the map I flashed on Sunday. Yesterday evening I flashed back to (almost) what I was using prior to seeing this issue, and the fuel trims are still going nuts. I'll post a log/chart from this morning's commute later today. http://uploads.tapatalk-cdn.com/20160927/796d1f39018107e080e8d5ead701cdf7.jpg My DiySB rebuild Got Misfires? Link to comment Share on other sites More sharing options...
heiche Posted September 27, 2016 Share Posted September 27, 2016 Pre-turbo vac leak? 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...
xt2005bonbon Posted September 27, 2016 Share Posted September 27, 2016 Pre-turbo vac leak? Link to comment Share on other sites More sharing options...
StkmltS Posted September 27, 2016 Author Share Posted September 27, 2016 (edited) I'm hoping that whatever created this new problem (high LVs) is THE thing I've been looking for this whole time, and now I'll finally be able to find the root cause of my misfire. Example: Maybe a component (sensor, wire, terminal, fitting, adapter, manifold, etc) somewhere in the engine bay has had a very small crack for a long time, and just now it finally decided to fully break, creating a large enough problem that I'll be able to find the failing component. Edited September 27, 2016 by StkmltS My DiySB rebuild Got Misfires? Link to comment Share on other sites More sharing options...
xt2005bonbon Posted September 27, 2016 Share Posted September 27, 2016 What do you mean it went kaput? The car JUST went kaput? I hope not... Link to comment Share on other sites More sharing options...
StkmltS Posted September 27, 2016 Author Share Posted September 27, 2016 It's still driving fine and it doesn't feel like it's adding 15% more fuel at idle. I edited my previous post, it should be more clear now. My DiySB rebuild Got Misfires? Link to comment Share on other sites More sharing options...
xt2005bonbon Posted September 27, 2016 Share Posted September 27, 2016 So, what are you next troubleshooting steps? Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now