iNVAR Posted April 7, 2013 Share Posted April 7, 2013 Okay, looked at your logs. 1) Doubtful you'd get knock from interference. Also, when was the last time you reset the ECU? All that learned knock is gone, which makes me think you reset it somewhat recently? 2) Most people like their AF trims to be between +/- 5%. Yours are about 6, which isn't too bad. Again, I don't like what your tuner did with essentially disabling Trim D, but whatever... a handful of people have done that before and have their reasons. I'm firmly againstit. Your MAF scaling might be off... or perhaps you have a leak of some sort, I'm not sure. 3) You are spooling and boosting like CRAP. And your logs show why: your WGDC is extremely low at the beginning and your TD is maxing out. Whether this is by design (your tuner) or because you have a leak of some sort, I have no idea, but you are nowhere near achieving your boost targets. Also, I'm looking at your targets and they seem pretty unrealistic to me personally. At a glance, you're calling for 16.2 PSI at 6KRPM... you are NOT going to squeeze that out of a VF40, certainly not in 3rd, and even if you could muster up the exhaust to do that in 5th, your turbo would be spinning so fast that it'd turn into a flamethrower. edit: Ah, yes, you have a VF52, just reviewed the thread. Makes more sense now. Still, you are missing your boost targets by quite a bit. You may have a boost leak, which is killing your spool, and causing you to miss your targets. Link to comment Share on other sites More sharing options...
RallyMachine Posted April 7, 2013 Author Share Posted April 7, 2013 Thanks Invar, glad to have my my logging issue resolved! I reset it last week but I'm not sure why the knock correction would go back to zero? I drove the car pretty hard today and figured it would have reestablished the correction if it was still knocking. Yeah I had a sneaking suspicion that my spool was screwed up... I've heard it's rare for VF52's but could this turbo be on its way out? I've been burning quite a bit of oil and can't figure out where it's going. Thought it might be a ringland but the car still pulls good. Maybe the turbo seals are crapping out? I guess a boost leak would be more likely, but I'm not sure where to start to look... Thanks again for your help! Link to comment Share on other sites More sharing options...
iNVAR Posted April 7, 2013 Share Posted April 7, 2013 You start looking for boost leaks by doing a boost leak test. Or you can try checking the usual suspects... TMIC connections (turbo and intake side), BPV gasket. Link to comment Share on other sites More sharing options...
RallyMachine Posted April 7, 2013 Author Share Posted April 7, 2013 Ok, will do. Took the TMIC off for the first time last week too to check for oil, so maybe i didn't get everything back on tight enough. Although my spool has always been kinda sh***y Link to comment Share on other sites More sharing options...
fahr_side Posted April 7, 2013 Share Posted April 7, 2013 Looks okay. Just keep an eye on those fuel trims. I like to see within -/+ 5% but trims do move around some just after a reset. 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...
RallyMachine Posted April 7, 2013 Author Share Posted April 7, 2013 So what exactly do the fuel trims do? Noob question sorry Link to comment Share on other sites More sharing options...
iNVAR Posted April 7, 2013 Share Posted April 7, 2013 http://legacygt.com/forums/showpost.php?p=4298782&postcount=23 Link to comment Share on other sites More sharing options...
RallyMachine Posted April 13, 2013 Author Share Posted April 13, 2013 So after I finally got my car back from the shop (transmission work) and did a pull to see if tightening down the i/c, turbo bolts, etc. did any good. If I'm interpreting this right, it looks like the car leaned out a bit compared to the slightly rich LV I pulled before. I did notice that the inlet clamp on the turbo was slightly loose...could this be a possible cause? Also, is positive A/F learning better than negative (just based on the red color of negative learning)? Thanks again guys! Link to comment Share on other sites More sharing options...
fahr_side Posted April 13, 2013 Share Posted April 13, 2013 You want to see small values, like under 5%. For safety, the system is usually biased slightly rich, meaning you'll see small negative trims to hit stoich. 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...
RallyMachine Posted April 13, 2013 Author Share Posted April 13, 2013 You want to see small values, like under 5%. For safety, the system is usually biased slightly rich, meaning you'll see small negative trims to hit stoich. Ok so as long as I'm not knocking and A/F learning is within 5% I should be alright? Link to comment Share on other sites More sharing options...
fahr_side Posted April 13, 2013 Share Posted April 13, 2013 That is considered a good sign. I also like to see logs to check for FBKC, which isn't shown in learned tables. 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...
Yfarmeaahka Posted August 29, 2013 Share Posted August 29, 2013 RallyMachine did you ever find the sourse of your knock or was it just a tuning issue? I am having a knock issue and cant seem to tune it all the way out without really tuning the car down. I'm on the vf40 with sti UP, cobb catted DP, AVO turbo inlet, and AVO TMIC. I believe I too may have an alternator issue. When my car idles down a lot of the time it dims the lights quite a bit. Sometimes it will drop idle low enough to stumble a bit and then the rpms jump up for just a second. Im going to test my alternator tonight with a multi tool. Link to comment Share on other sites More sharing options...
RallyMachine Posted August 29, 2013 Author Share Posted August 29, 2013 No not really... I think it was a combination of temperature changes and small leaks. Yours definitely sounds like it could be an alternator issue if your lights are dimming at idle. Link to comment Share on other sites More sharing options...
Yfarmeaahka Posted August 29, 2013 Share Posted August 29, 2013 Yeah I'll be finding out tonight. it doesnt make any noise even if I use a stethiscope on it so im not convensed thats whats causing my knock though. Link to comment Share on other sites More sharing options...
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