monkonmonk Posted September 13, 2011 Share Posted September 13, 2011 Hey guys, I have been trying to read a bit lately on boost leaks and such as that is what I thought was wrong with my car. It all started yesterday, I noticed that the car felt a bit slower. I started watching my lossol built boost gauge and saw that in all modes I was only reaching half of the targeted boost. I also confirmed that in 'S' and 'S#' I also was only reaching half of the targeted boost. 4psi in 'I' mode and about 9-10psi in 'S' and 'S#'. I am currently Stg2 with an Infamous tune, AVO panel, AVO TMIC, Cobb DP, SPT SBE. I am getting no strange noises from the car such as would be suspsect from a boost leak. But, I would think that with a boost leak I would be able to maintain some certain pressure for both I mode and S mode. Seeing as how they are different makes me think it is something else. On the way to work this morning I took a LV after I go to work, about 4.4 miles. The log is just before the learning view in which I tried to capture if anything was going on with the car. S# pull limited by traffic. Any ideas? Jason Any ideas?romraiderlog_20110913_074545.csv Link to comment Share on other sites More sharing options...
compsurge Posted September 13, 2011 Share Posted September 13, 2011 Your IAM is 0. You are in limp mode. Check for pre turbo leaks (inlet tube), check your BOV vacuum/pressure line as it may have come undone (and will cause the pressure to build, then bleed quickly. Your turbo could be seizing - any bad noises/squeals? Link to comment Share on other sites More sharing options...
bmx045 Posted September 13, 2011 Share Posted September 13, 2011 your car runs? Link to comment Share on other sites More sharing options...
monkonmonk Posted September 13, 2011 Author Share Posted September 13, 2011 I will go out to the parking lot and give those a look. no noise whatsoever. Car sounds normal other than holding itself back. The other strange thing is yesterday for about a 1.0 miles stretch the car drove normal with normal boost levels and I thought everything was fixed. Drove it again about 3 hours later and back to 'limp mode' (learn something new everyday! - thanks compsurge). Monk Link to comment Share on other sites More sharing options...
bmx045 Posted September 13, 2011 Share Posted September 13, 2011 limp mode makes you run wastegate boost, usually 6psi or so. So the cause of the holding back could be something else. also, enable the DTC code reader at the bottom of LV Link to comment Share on other sites More sharing options...
monkonmonk Posted September 13, 2011 Author Share Posted September 13, 2011 your car runs? Barely....but startup and boost free or low boost driving is no problem. Drives pretty normal actually. i will check the oil situation too. monk Link to comment Share on other sites More sharing options...
compsurge Posted September 13, 2011 Share Posted September 13, 2011 I am all too familiar with limp mode. You will need to do some logging. Your knock sum seems to stay steady under load, which is good; however, do some low load logging when you get a chance. Check/clean your MAF as well (just an easy thing to check). How are plugs? Another place to check for leaks is post intercooler - do you have an AVO tb hose? Also check the infamous T pressure line under the intercooler (will require removal of the intercooler most likely). It has a tendency to blow off if not zip tied. Link to comment Share on other sites More sharing options...
monkonmonk Posted September 13, 2011 Author Share Posted September 13, 2011 I am all too familiar with limp mode. You will need to do some logging. Your knock sum seems to stay steady under load, which is good; however, do some low load logging when you get a chance. Check/clean your MAF as well (just an easy thing to check). How are plugs? Another place to check for leaks is post intercooler - do you have an AVO tb hose? Also check the infamous T pressure line under the intercooler (will require removal of the intercooler most likely). It has a tendency to blow off if not zip tied. I can do some low load logging at lunch. As well as clean the MAF sensor. No AVO TB hose for me, just the factory one. I will confirm the T-pressure line under the TMIC, but I am pretty sure I remember zip-tying that one. limp mode makes you run wastegate boost, usually 6psi or so. So the cause of the holding back could be something else. also, enable the DTC code reader at the bottom of LV I will do that at lunch. Thanks for all the quick replies, fellas. Monk Link to comment Share on other sites More sharing options...
monkonmonk Posted September 13, 2011 Author Share Posted September 13, 2011 Alright, here is what I think are low load pulls (just cruising?). And a LV with DTC enabled. Also, I have not reset the ECU yet. I am going to check those hoses and such right now. Monk Link to comment Share on other sites More sharing options...
bmx045 Posted September 13, 2011 Share Posted September 13, 2011 reset the ecu then do some wot pulls, then post a lv again Link to comment Share on other sites More sharing options...
monkonmonk Posted September 13, 2011 Author Share Posted September 13, 2011 After the ECU Reset, I immediately took a learning view to show the 0.75 IAM. Then, I took some wide open logs as shown, again limited by traffic and posted speed limits. Lastly, I arrived at work and took another LV, which was 0.6875. I found no hoses to be disconnected or anything amiss. I did not have time to remove the TMIC just yet, but I was at least back to somewhat normal boost levels after the reset. I seemed to have missed the new LV. Can I just go back out to the car and take it again, even though i shut the car off? Monk Link to comment Share on other sites More sharing options...
bmx045 Posted September 13, 2011 Share Posted September 13, 2011 I do not suspect a vaccum leak or a popped off hose seeing as your fuel trims are within +/- 5%. .75 is probably the initial IAM starting point. It should slowly rise to 1 in a typical environment. where's the .68 screenshot? Link to comment Share on other sites More sharing options...
monkonmonk Posted September 13, 2011 Author Share Posted September 13, 2011 It must not have saved when I finished. It was basically all zeros except for the 1.65-2.00 and 3600-4200 box showed a -1.40 in red. I should be able to go right back out to the car and get that same data right? Start it or no? Link to comment Share on other sites More sharing options...
compsurge Posted September 13, 2011 Share Posted September 13, 2011 Those logs tell me to stay out of boost since it's detecting knock WOT. Have you pressure tested the system for leaks? Link to comment Share on other sites More sharing options...
bmx045 Posted September 13, 2011 Share Posted September 13, 2011 how long has it been acting up like this? have you ever done a LV before this episode? real bad gas can cause knock all over the place. seeing a -1.40 means it knocked very recently. the ecu slowly attempts to advance timing....so seeing anything closer to 0 from -1.40 means the ecu added that timing. seeing -2.80 means you knocked twice very recently. essentially everytime your knock sensor triggers, it pulls -1.40...so by simple math...you can determine where's you're at. Link to comment Share on other sites More sharing options...
monkonmonk Posted September 13, 2011 Author Share Posted September 13, 2011 It started acting like this yesterday. Last I drove it before that was Friday and it was just fine. Nothing wrong. I simply started in Monday morning, drove to work and had the lower boost happen. No LV since the final revision of the tune. Infamous informed to take one once the weather cooled down since my tune was done in high heat and humidity. But, it is still hot here in OH. I will add the LV from right after the tune. Monk Link to comment Share on other sites More sharing options...
compsurge Posted September 13, 2011 Share Posted September 13, 2011 You also need to log fewer parameters to get a better cycle rate Just delete the 4 byte redundants Link to comment Share on other sites More sharing options...
monkonmonk Posted September 13, 2011 Author Share Posted September 13, 2011 LV from original tune added... So, basically about 5 months. Link to comment Share on other sites More sharing options...
monkonmonk Posted September 13, 2011 Author Share Posted September 13, 2011 will do. I will take some more logs later this afternoon. Any idea what could be causing it? Bad gas? Oil? I have not tested the system for leaks yet with any sort of smoking or other method. Link to comment Share on other sites More sharing options...
bmx045 Posted September 13, 2011 Share Posted September 13, 2011 if it's a new onset, I suspect bad gas. Drive it empty and fill it up with shell Link to comment Share on other sites More sharing options...
compsurge Posted September 13, 2011 Share Posted September 13, 2011 +1 Bad gas makes sense in this case. If it exists after this tank, something might be up. Don't reset the ECU - see if it fixes itself in the logs. Link to comment Share on other sites More sharing options...
monkonmonk Posted September 13, 2011 Author Share Posted September 13, 2011 So basically, avoid boost, monitor LV, log daily (even commute driving?), and then fill up with good gas to see if it goes away. What about octane booster or something to fix the bad gas? Thanks again for all the help. monk Link to comment Share on other sites More sharing options...
bmx045 Posted September 13, 2011 Share Posted September 13, 2011 try to get rid of that gas asap without getting much into boost Link to comment Share on other sites More sharing options...
compsurge Posted September 13, 2011 Share Posted September 13, 2011 You can try adding some seafoam to the tank. I haven't found octane booster to do much of anything. Maybe racing fuel Link to comment Share on other sites More sharing options...
monkonmonk Posted September 13, 2011 Author Share Posted September 13, 2011 I can buy 105octane at a gas station not too far from where I live. Maybe that would work. i have some seafoam at home. I will see how much fuel I have left in the tank. Link to comment Share on other sites More sharing options...
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