blongo804 Posted May 19, 2011 Share Posted May 19, 2011 UPDATE ON BOTTOM Well, that's the best way I can describe it. A little background info.. I just put a plethora of parts on the car Saturday. SRI (although the SRI was previously installed) TMIC, UP/DP/CBE, EBCS, and a lightened crank pulley and got my tune. As we were driving the car, not only does it pull really hard now, but it also has a studder when it climbs the power band. It seems to quickly studder-rev around the upward of 3.5-4k (maybe even a little higher). The tuner suggests checking for a vacuum leak, saying a certain hose directly under the TMIC commonly pops off. That is my first place to check. A friend suggested it may be the torque converter but it depends on the load for that. So I'm going to do a little investigating today after school. Anyone else have some suggestions? I'm sure it can be a bunch of other things unfortunately lol. Thanks in advance! Link to comment Share on other sites More sharing options...
bmx045 Posted May 19, 2011 Share Posted May 19, 2011 Well a vac leak should be obvious at idle- and the tuner would confirm that while logging. Also, you'll likely be underboosting. The hose that he mentioned is the hose that feeds your bpv, mine popped off during the stage 2 tune, it caused the bpv to prematurely release and vent boost out- along with rough lumpy idle. It's probably not the torque converter but a log would help us all out if you could post it up. If you didn't do a boost leak test after installing all that mumbo-jumbo then there's a good chance you're leaking like my ass after mexi-taco night... Link to comment Share on other sites More sharing options...
blongo804 Posted May 19, 2011 Author Share Posted May 19, 2011 If you didn't do a boost leak test after installing all that mumbo-jumbo then there's a good chance you're leaking like my ass after mexi-taco night... Well now that you mention...lol. Thank you for the detailed advice on what to look for. I can definitely imagine what you're saying. Idle is kind of vibrate-y but I just figured that was the typical rumble. Idle rpm is good still. How do I put a log up? Just copy/paste the table of numbers? One thing I should probably note is that it was doing this studder with the base map and 1st revision. Link to comment Share on other sites More sharing options...
ShadowImg Posted May 19, 2011 Share Posted May 19, 2011 If you're revving to expected boost levels and it's falling on its face as it hits them, you need to make sure it's not detecting detonation. What kind of data do you have? Do you have a wideband or anything? Link to comment Share on other sites More sharing options...
bmx045 Posted May 19, 2011 Share Posted May 19, 2011 Well now that you mention...lol. Thank you for the detailed advice on what to look for. I can definitely imagine what you're saying. Idle is kind of vibrate-y but I just figured that was the typical rumble. Idle rpm is good still. How do I put a log up? Just copy/paste the table of numbers? One thing I should probably note is that it was doing this studder with the base map and 1st revision. When you log, it saves as a .csv file, just attach the file (see the bottom where you can add attachments) make sure to log while at idle and at full throttle. you'll want these parameters- engine load, engine speed, ignition total timing, IAT, knick sum(if avail), manifold relative pressure corrected, mass airflow g/s, primary wastegate duty cycle, target boost, throttle opening plate(angle) Link to comment Share on other sites More sharing options...
Max Capacity Posted May 19, 2011 Share Posted May 19, 2011 My Tuner told me to zip tie all the hoses. On the last street tune, I asked him if he could fix the studdering. We did a few 3rd gear and 4th gear pulls so he could see what was happening. He made some adjustments and all is fine. http://www.tuningalliance.com Let Mike know where you got this from. 305,600miles 5/2012 ej257 short block, 8/2011 installed VF52 turbo, @20.8psi, 280whp, 300ftlbs. (SOLD). CHECK your oil, these cars use it. Engine Build - Click Here Link to comment Share on other sites More sharing options...
blongo804 Posted May 19, 2011 Author Share Posted May 19, 2011 If you're revving to expected boost levels and it's falling on its face as it hits them, you need to make sure it's not detecting detonation. What kind of data do you have? Do you have a wideband or anything? No wideband. I can supply RomRaider logs though. I sure hope there's no detonation going on. When you log, it saves as a .csv file, just attach the file (see the bottom where you can add attachments) make sure to log while at idle and at full throttle. you'll want these parameters- engine load, engine speed, ignition total timing, IAT, knick sum(if avail), manifold relative pressure corrected, mass airflow g/s, primary wastegate duty cycle, target boost, throttle opening plate(angle) Gotcha. Thanks again for the help! I'll be getting these logs today after school. We have to do another WOT pull today anyways. My Tuner told me to zip tie all the hoses. On the last street tune, I asked him if he could fix the studdering. We did a few 3rd gear and 4th gear pulls so he could see what was happening. He made some adjustments and all is fine. http://www.tuningalliance.com Let Mike know where you got this from. I'll probably end up zip tying all the hoses just to be safe. Thanks for the link I'll check into it when I get a chance! Link to comment Share on other sites More sharing options...
ShadowImg Posted May 19, 2011 Share Posted May 19, 2011 Check your knock sum/knock correction BEFORE you do another WOT pull. If it's retarding because of that, you don't want to keep doing it. Link to comment Share on other sites More sharing options...
bmx045 Posted May 19, 2011 Share Posted May 19, 2011 Check your knock sum/knock correction BEFORE you do another WOT pull. If it's retarding because of that, you don't want to keep doing it. not to send this off-topic but, when I did a 3rd gear pull from 2k-6k, with my 5EAT, I noticed my knock sum would fluctate and eventually ending up at 7, however my FLKC and FBKC were 0 all the time....this was right after an ecu reset. does this seem odd? perhaps crappy gas? how is it summing knocks if the FBKC doesn't detect any? Link to comment Share on other sites More sharing options...
ShadowImg Posted May 19, 2011 Share Posted May 19, 2011 Honestly can't say -- I'd assume there's some levels of margin of error between knock sum and actual correction. I don't know where that level lies. Maybe ask someone like Infamous? Link to comment Share on other sites More sharing options...
blongo804 Posted May 20, 2011 Author Share Posted May 20, 2011 Ok i'm back with problems... Good news = No knock! Woo! Good news #2 = Found a detached vacuum line and secured it in. Woo! BAD NEWS = Still studders, but with that comes video. Two videos to be exact. I try my best to get the sound, it is tough and only an iphone. NOTICE THE WASTEGATE FLUTTER: (you can hear that the best in the video. In real life it's both that and the engine revving, then bog, rev, bog, etc..) [ame=http://www.youtube.com/watch?v=zYLnR6xiclQ]YouTube - LGT Flutter[/ame] [ame=http://www.youtube.com/watch?v=8cnPAxy78CA]YouTube - LGT Flutter 2[/ame] Link to comment Share on other sites More sharing options...
blongo804 Posted May 20, 2011 Author Share Posted May 20, 2011 Bump! Link to comment Share on other sites More sharing options...
blongo804 Posted May 22, 2011 Author Share Posted May 22, 2011 Figured it out! Tuner says it's the Perrin intake making the car run rich and making it stumble upon boost transition..sounds right to what I'm feeling. Link to comment Share on other sites More sharing options...
JoeFromPA Posted May 22, 2011 Share Posted May 22, 2011 Sounds like the tuner doesn't know how to tune for an intake on these cars.... Link to comment Share on other sites More sharing options...
blongo804 Posted May 23, 2011 Author Share Posted May 23, 2011 He does. This intake is just hard to tune with because of the crappy MAF placement in the bend. Link to comment Share on other sites More sharing options...
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