Apexofthevortex Posted November 24, 2015 Share Posted November 24, 2015 I'm gonna bring it back to what Brandon mentioned a while ago regarding the traction control possibly cutting in. Thinking about it logically, if the engine is making power and the drive-train can move freely without slipping somewhere or some kind of mechanical obstruction that would leave only your tires or something electrical getting in the way. I think tires would be pretty obvious if they were the culprit, but I think it would be possible for TC to be holding you back. If you haven't already I'd try unplugging the ABS wheel sensors. I think I speak for everyone when I say we're all pulling for you, what that one dude said about this thread being like a netflix drama with no last episode is so true. Link to comment Share on other sites More sharing options...
jackal8788 Posted November 24, 2015 Author Share Posted November 24, 2015 Didn't this all start from a 15 WRX that was supposedly stock pulling on you like you were standing still? Since you've gone over nearly everything on your car I think it's safe to say that the WRX owner was playing the sleeper role. It's likely a 500whp car. Just throwing some humor/smartassness into the mix here...seems outrageous that you've found anything yet! Good luck in your search jackal8788! LOL. Yeah, she may have snuck one past me. She's the craftiest mom I know But seriously, appreciate a little levity in the mix. It is needed at this point! I'm gonna bring it back to what Brandon mentioned a while ago regarding the traction control possibly cutting in. Thinking about it logically, if the engine is making power and the drive-train can move freely without slipping somewhere or some kind of mechanical obstruction that would leave only your tires or something electrical getting in the way. I think tires would be pretty obvious if they were the culprit, but I think it would be possible for TC to be holding you back. If you haven't already I'd try unplugging the ABS wheel sensors. I think I speak for everyone when I say we're all pulling for you, what that one dude said about this thread being like a netflix drama with no last episode is so true. Thanks for bringing this back up - I will add this to our test plan just to rule it out since it's a simple thing to check. Appreciate all the comments, both helpful and humorous (which are in turn, also helpful). We'll get there yet VF54 to 20G to VF54 to 18G build thread Link to comment Share on other sites More sharing options...
jackal8788 Posted November 24, 2015 Author Share Posted November 24, 2015 What if the issue isn't a broken valve spring but just weak valve springs? Then the car might idle fine and run reasonably well at lower RPMs. It still doesn't miss or run rough at higher RPMs, just runs out of power...Hmmmm........something else to check? VF54 to 20G to VF54 to 18G build thread Link to comment Share on other sites More sharing options...
Apexofthevortex Posted November 24, 2015 Share Posted November 24, 2015 What if the issue isn't a broken valve spring but just weak valve springs? Then the car might idle fine and run reasonably well at lower RPMs. It still doesn't miss or run rough at higher RPMs, just runs out of power...Hmmmm........something else to check? Maybe a dumb question, but have you gotten back on a dyno since this started happening to see how much power or torque you've actually lost? I know some shops will sell single pulls for around 120 bucks so you don't have to pay the full price for a protune. Link to comment Share on other sites More sharing options...
cww516 Posted November 24, 2015 Share Posted November 24, 2015 I was kinda wondering if there was any way the valves could be getting hung up, maybe staying open a little longer than they should be and allowing a little bit of air to be pushed back out on the compression stroke, which would probably manifest itself in about the same way as weak springs, but with the addition of some nasty looking wear marks on the valve stems. Just spitballing, though. I still think it sounds like the issue should be in the intake tract somewhere between the throttle plate and the tops of the pistons- the fact that you're hitting your boost target and getting there quicker than normal sounds similar to dead-heading a pump or covering the outlet of a fan. Link to comment Share on other sites More sharing options...
LatentWagen Posted November 24, 2015 Share Posted November 24, 2015 ...what that one dude said about this thread being like a netflix drama with no last episode is so true. This thread belongs on daytime TV Will it be an intake blockage? Maybe a drive-line gremlin? What about a hitch-hiking baby elephant? Or, perhaps, a bunched up floor mat under the gas pedal? ... Will the problem ever be found?! All this, and more, on the next episode of... The Bold and The Boosted LW's spec. B / YT / IG Link to comment Share on other sites More sharing options...
FLlegacy Posted November 24, 2015 Share Posted November 24, 2015 If traction control was stepping in the light would be flashing. And if the valve springs were weak the leak down test would have discovered them. Sent from my SAMSUNG-SGH-I337 using Tapatalk Link to comment Share on other sites More sharing options...
jackal8788 Posted November 24, 2015 Author Share Posted November 24, 2015 (edited) Maybe a dumb question, but have you gotten back on a dyno since this started happening to see how much power or torque you've actually lost? I know some shops will sell single pulls for around 120 bucks so you don't have to pay the full price for a protune. I haven't been on the dyno, but I've put my datalogs into Virtual Dyno. I found it to be pretty accurate when I tested it shortly after my original dyno tune and when doing the same pull on the same road, it showed a reduction in peak HP of over 50%. I know it isn't as good as an actual dyno but I wanted to do something a little less subjective than just saying 'it feels more sluggish'. Another supporter for the lost power is the acceleration from the datalogs. After the tune in 3rd gear at WOT, the climb from 30 MPH - 70 MPH took ~4.5 seconds. Under the same conditions, that now takes just over 11 seconds. Definitely not a dumb question. At this point, I'm just saving my cash for the diagnostics and repair work. Edited November 24, 2015 by jackal8788 VF54 to 20G to VF54 to 18G build thread Link to comment Share on other sites More sharing options...
jackal8788 Posted November 24, 2015 Author Share Posted November 24, 2015 If traction control was stepping in the light would be flashing. And if the valve springs were weak the leak down test would have discovered them. Sent from my SAMSUNG-SGH-I337 using Tapatalk Would a leakdown test necessarily uncover weak valve springs though? The springs may still be strong enough to close/seat the valves and once pressure is applied, it will only serve to close the valves more right? VF54 to 20G to VF54 to 18G build thread Link to comment Share on other sites More sharing options...
jojorios Posted November 24, 2015 Share Posted November 24, 2015 I think it's time to replace the hamster in the turbo... Link to comment Share on other sites More sharing options...
s2baru Posted November 24, 2015 Share Posted November 24, 2015 This isn't a kia Link to comment Share on other sites More sharing options...
LatentWagen Posted November 24, 2015 Share Posted November 24, 2015 About the valve spring theory... each spring would have to fail/weaken the exact same amount, just enough to make you lose massive power but show no symptoms. It'd have to have been a bad batch that fatigued early, and all together. Long, long odds. Also long odds, but maybe someone is screwing with you, and contaminated your fluids or something. Is your car parked accessibly? Checked trans or rear diff fluid lately? I think it's time to replace the hamster in the turbo... Could also be his trunk monkey is on strike LW's spec. B / YT / IG Link to comment Share on other sites More sharing options...
brandon.mol Posted November 27, 2015 Share Posted November 27, 2015 I still think the problem is a busted differential that's pissing power away. The car is moving purely because of the VC. 11 seconds to 60 is like 160 horse territory and there is no way you are making full boost, proper afrs, proper maf, map, and not actually making the power. Except maybe charge temp. The only thing that makes sense to me is that power is getting lost after the motor. Did you check to make sure there was expected torque transfer sides to side at each axle and front to back? One other thing. What if your air charge temperature s are crazy high for some reason. Your car would make way less power but not report it anywhere since the iat sensor is in the maf. Boost would be fine. Afrs fine since less fuel required, but I would think your fuel trims would go seriously negative. Link to comment Share on other sites More sharing options...
s2baru Posted November 28, 2015 Share Posted November 28, 2015 Smoke test? Link to comment Share on other sites More sharing options...
jackal8788 Posted November 28, 2015 Author Share Posted November 28, 2015 Sorry, been away for a little with with the holiday but I do have some news although somewhat puzzling. We found that the compressor outlet gasket and the BOV O-ring were actually leaking. This was not found in the first leak test. In any case, replacement of the gasket and O-ring seem to have provided a noticeable difference in power. However, when I took a datalog I saw something I've not seen before. Today for the first time, my throttle position did not match my accelerator position. In all previous logs (including earlier logs with the low power issue) 100% accelerator position corresponded to 100% throttle position. Now when I am at 100% accelerator position, the throttle position starts at ~40% and it slowly works its way up to about 87%. What does this mean? Is the throttle plate having some kind of extremely delayed response? I'm glad to see something like this happening but I don't have the knowledge to know what it means <hint hint>. Any ideas? Log is attached for reference. One additional thing to note is that this is a log from a very mild 91 octane tune so it should not be directly compared to any previous postings from e85.91 octane power check.csv VF54 to 20G to VF54 to 18G build thread Link to comment Share on other sites More sharing options...
fahr_side Posted November 29, 2015 Share Posted November 29, 2015 (edited) Boost leaks will usually make your fueling rich, which of course will cost you power. They will also inflate your MAF numbers. As to your accelerator pedal position vs. throttle plate position... you would have to open your map and see first what Requested Torque figure corresponds to 100% pedal angle at rpm blocks (which are as stock) 2k8rpm to 5k2rpm. Then check to see if those values are smaller or larger than the values per rpm block in what in opensource we call the Requested Torque Base (RPM) table. Simply put, if the RT value from the pedal angle table is more than the RT Base value, the throttle plate position should be at 100% Example. RT table A. RPM 3k2, pedal angle 100%, RT value 380. RT Base table, 3k2rpm, RT value 348. 380 > 348, throttle angle should be 100%. Note there are reasons a tuner may not allow 100% throttle angles at lower rpm. I've personally never seen a map set where 100% throttle angle was not available until beyond 2k8rpm or so. I note your throttle angle peaks at 87.84% and holds there until you've let off. Are you sure you don't have some kind of valet map loaded? Sent from a device using some software. Edited November 29, 2015 by fahr_side 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...
LatentWagen Posted November 29, 2015 Share Posted November 29, 2015 And your turbo has been working *extra* hard to make that target boost. Hotter air from the compressor means more knock and less power. That bit makes sense. However, IIRC you said your turbo was spooling sooner, which wouldn't be indicative of a boost leak. Strange. But, if it's fixed, it's fixed! Time for dancing :banana: LW's spec. B / YT / IG Link to comment Share on other sites More sharing options...
s2baru Posted November 29, 2015 Share Posted November 29, 2015 One thing for the throttle response I know some people have that "delay" of full throttle but only 60-80% vaues come on to help with economy type maps so you're not to peaky to on&off boost response to help with mpgs. But I'd be confused as to why someone would do that intentionally like what fahr_side said Link to comment Share on other sites More sharing options...
jackal8788 Posted November 29, 2015 Author Share Posted November 29, 2015 My friends, I hate to conclude the soap opera that has been my car's impotence (not really because it finally means I have my ride back) but I can report that after filling up with e85 today and reflashing that map, we are 100% back in business!! Thank you for your help, comments, and humor. I appreciated this community before but I am truly thankful to you all and I hope that this provides some help for other folks in case they find themselves in a similar situation. Cheers! VF54 to 20G to VF54 to 18G build thread Link to comment Share on other sites More sharing options...
GTEASER Posted November 29, 2015 Share Posted November 29, 2015 So what was the problem? GTEASER's 2012 Legacy GT - Sold GTEASER's 2009 XTeaser - Sold GTEASER's 1992 Legacy SS - Sold Link to comment Share on other sites More sharing options...
jackal8788 Posted November 29, 2015 Author Share Posted November 29, 2015 So what was the problem? I can't say for sure that it was one single thing because we did note marked improvement from the TGV delete, though it seemed that the root cause was boost leak. The replacement of the compressor outlet gasket and the BOV O-ring really made the major difference. I wish I could tell you why these didn't show as leak points during the original boost leak test but I don't know why. I also don't know why my AFRs appeared to be normal with this happening. I can understand still hitting boost targets - the turbo may be able to compensate at the expense of a hotter charge, but I can't explain why I didn't see this on my wideband as frequent rich conditions when in open loop. VF54 to 20G to VF54 to 18G build thread Link to comment Share on other sites More sharing options...
Shadow_419 Posted November 29, 2015 Share Posted November 29, 2015 While I'm glad you were able to get your issue resolved, I'm going to miss this thread. It was a must read. I can't even begin to imagine how frustrating this whole process has been. Link to comment Share on other sites More sharing options...
jackal8788 Posted November 29, 2015 Author Share Posted November 29, 2015 While I'm glad you were able to get your issue resolved, I'm going to miss this thread. It was a must read. I can't even begin to imagine how frustrating this whole process has been. Lol! I appreciate the comments. It surely was frustrating but it has made me appreciate my car and this forum even more and without incurring massive expenses so overall I think this is a good thing. As for more drama, well, I wouldn't worry. The Panda knows what it's doing Sent from my iPhone using Tapatalk VF54 to 20G to VF54 to 18G build thread Link to comment Share on other sites More sharing options...
FLlegacy Posted November 29, 2015 Share Posted November 29, 2015 Time to call up that impreza for a rematch! Sent from my SAMSUNG-SGH-I337 using Tapatalk Link to comment Share on other sites More sharing options...
rebourne Posted November 30, 2015 Share Posted November 30, 2015 Hallelujah!! pic thread build thread Link to comment Share on other sites More sharing options...
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