BehindTheLens Posted January 5, 2018 Share Posted January 5, 2018 Hey all! I'm new to both this forum and the cobb AP. I have a 2009 Outback XT and just loaded the OTS stage 1 map from cobb. Everything else is completely stock. As soon as I go WOT, the boost spikes up to 18ish psi and then settles back out to around 15. Is that normal? I tried both the low waste gate and normal waste gate maps and they had the same results. I've attached a datalog of a WOT 3rd gear pull if anyone more knowledgable can take a look and let me know what you think. Thanks guys! Mattdatalog29.csv Link to comment Share on other sites More sharing options...
relative4 Posted January 6, 2018 Share Posted January 6, 2018 Target boost is 16 PSI, so that is somewhat worrisome. Some possible causes of overboost on completely stock hardware: Sticky wastegate Bad wastegate actuator Failing boost control solenoid Leaky or clogged boost control hose Other vacuum leaks I'd start with a smoke test. Boosting 18 PSI on a non-bulletproofed stock TMIC, chances are you've split that sucker pretty good. Running 11-12% lean at idle tends to support that notion. Then I'd test wastegate actuation. Link to comment Share on other sites More sharing options...
BehindTheLens Posted January 6, 2018 Author Share Posted January 6, 2018 Thanks relative4! Is there a way to fix a sticky waste gate or bad actuator or do I need to buy a new one if that is the case? And are you seeing the 11-12% lean at idle in my logs or is that something I should check for? This is my first turbo car, so totally new to all this. Link to comment Share on other sites More sharing options...
robburns201 Posted January 6, 2018 Share Posted January 6, 2018 is there a high wastegate setting? I believe the High one is if you are having higher than normal boost... Link to comment Share on other sites More sharing options...
xt2005bonbon Posted January 6, 2018 Share Posted January 6, 2018 If the 'high wastegate setting' refers to higher wastegate duty cycles, then that would mean that it would tend to increase even more the boost level since higher wastegate duty cycle means the wastegate will be closed for a longer period of time. Conversely, lower wastegate DC would then tend to favor lower boost level since it would free up some of the exhaust through the wastegate. Conclusion: if you are overboosting, then perhaps the wastegate DC needs to be lowered. Also, keep in mind that it is cold right now. That favors overboosting too, at least in my case, it does. Do you have an aftermarket air intake? Link to comment Share on other sites More sharing options...
relative4 Posted January 6, 2018 Share Posted January 6, 2018 Is there a way to fix a sticky waste gate or bad actuator or do I need to buy a new one if that is the case? Find the problem before worrying about how to fix it. are you seeing the 11-12% lean at idle in my logs or is that something I should check for? Some very useful learned values are fuel learning A through D. A being idle, higher letters for higher flow. As you travel up/down through the RPM range, the ECU applies the fuel trims it's learned from earlier visits to that range. The fuel trim currently applied is logged in the A/F Learning 1 column. At the end of your log, as you drop down almost to idle, the fuel trim goes to 11.72, indicating that your fuel learning A value is that or possibly higher. If you pull the fuel learning A through D values via the AP, that will provide a good starting point for diagnosis and testing. Link to comment Share on other sites More sharing options...
relative4 Posted January 6, 2018 Share Posted January 6, 2018 is there a high wastegate setting? I believe the High one is if you are having higher than normal boost... https://www.cobbtuning.com/subaru-ots-maps-high-wastegate-low-wastegate-normal-wastegate/ Link to comment Share on other sites More sharing options...
BehindTheLens Posted January 8, 2018 Author Share Posted January 8, 2018 UPDATE: I think I may have figured out the boost spike. The hose from the intercooler to the throttle body was loose. Tightened it, went through all the other connections making sure everything was tight and then left the heat shield off because it looked super close to the waste gate actuator arm and I thought it could be hitting (does that happen?) Reflashed the map and only went above target once to 16.08psi. It's 40 degrees out so I thought that seemed reasonable? Anyway, does that sound like the spike problem is fixed? Here is an updated log. I still need to add the fuel learning values, but how does it look other than that? Thanks again, I really appreciate the help! https://docs.google.com/spreadsheets/d/1IpqOIfKoCrXUqAmjzIEaOnKvpGcN0B59mKm84x9R1wE/edit?usp=sharing Link to comment Share on other sites More sharing options...
relative4 Posted January 8, 2018 Share Posted January 8, 2018 Nice work, that IC-TB leak is a common one. Never heard of an actuator hitting the heat shield, is the heat shield bent? The log looks great, only issue is the 7% fuel learning in the B range. That may still be coming down if you did your pull shortly after fixing the leak. No, if you did a reflash rather than a realtime, you would have reset that to zero. So worth looking into. A smoke test would be a good idea, take a look at the front passenger corner of the TMIC and see if the sealing tabs are bending open. If you don't have access to a smoke tester and don't want to spend $80 to buy one, I can knock it out in 10 minutes if you're near the tech center sometime. When you're ready to get serious about making your XT perfect, Cryotune is in Arvada. Link to comment Share on other sites More sharing options...
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