praedet Posted April 3, 2009 Share Posted April 3, 2009 All right, as I go into my install this weekend, I am trying to diagnose a problem I have had for a long time... So, this all started back when I switched from TMIC to FMIC on the VF40. No matter how much boost I request, I get roughly 11-12 psi as mw max. This is with running the WGDC as high as 95 w/ boost targets of 15-16 psi. Since the first real sign of this problem, here are the multiple set-ups I have had where the problem was still present. VF40, FMIC, GFB BOV on full recirc, Pro-drive BCS VF40, FMIC, GFB BOV on full recirc, Stock BCS VF40, AVO TMIC, GFB BOV on full recirc, Stock BCS VF40, Stock TMIC, GFB BOV on full recirc, Stock BCS VF40, AVO TMIC, Stock BPV, Stock BCS So, what do you all think. Is it a leak somewhere? I am about to do an STi swap and I would love to have some idea what to fix, or if this will go away, before I do it... Thanks, Ted Link to comment Share on other sites More sharing options...
praedet Posted April 3, 2009 Author Share Posted April 3, 2009 I moved it to tuning, but I don't know if that is where it should go... Link to comment Share on other sites More sharing options...
Speedracerx Posted April 3, 2009 Share Posted April 3, 2009 Are you still running the stock "pill" in the boost signal line? Link to comment Share on other sites More sharing options...
Legend Posted April 3, 2009 Share Posted April 3, 2009 Actuator on the VF40? Probably not a tuning issue, but you could find out for sure by logging MRP, WG, target boost, TDint, and TDprop... but if your ecu is reporting WG pegged at 95% then the tune is doing everything it can to increase boost. My '05 LGT My '07 Supercharged Shelby Link to comment Share on other sites More sharing options...
rao Posted April 3, 2009 Share Posted April 3, 2009 Are you still running the stock "pill" in the boost signal line? +1, you need a smaller restrictor. To test for sure disconnect the tube that goes to the waste gate and BE CAREFUL! Odds are that you will see plenty of boost. Rob IF YOU CARE ABOUT YOUR CAR YOU SHOULD NEVER DRIVE IT Link to comment Share on other sites More sharing options...
tommypenguin Posted April 3, 2009 Share Posted April 3, 2009 What is your vacuum reading at idle in the logs? Gotten to do a pressure test? Link to comment Share on other sites More sharing options...
praedet Posted April 4, 2009 Author Share Posted April 4, 2009 Vacuum on the COBB, or my gauge... I believe it is roughly 17-18 mmhg on the gauge at idle... I understand how the pill would be an issue, but then why was I able to hit 17psi out here before the FMIC install, and not able to hit above 11 w/ the Prodrive EBCS as I increased Duty cycle? Link to comment Share on other sites More sharing options...
praedet Posted April 4, 2009 Author Share Posted April 4, 2009 Oh yeah, I am stock pill now... Link to comment Share on other sites More sharing options...
fonts Posted April 4, 2009 Share Posted April 4, 2009 Did you change the spring in the BOV to a softer spring when you went with the FMIC?? Link to comment Share on other sites More sharing options...
praedet Posted April 4, 2009 Author Share Posted April 4, 2009 Yes, but I am back on the stock BPV now... Link to comment Share on other sites More sharing options...
NSFW Posted April 4, 2009 Share Posted April 4, 2009 Any issues with the way the car runs, other than low boost? CELs, rough idle, bad mileage, etc? Link to comment Share on other sites More sharing options...
caramall2 Posted April 4, 2009 Share Posted April 4, 2009 +1 ...but like he said, be very careful....boost will shoot up fast. As soon as you see it get to 17 or so, let off quick. Then you know it's a control issue. To test for sure disconnect the tube that goes to the waste gate and BE CAREFUL! Odds are that you will see plenty of boost. Link to comment Share on other sites More sharing options...
praedet Posted April 4, 2009 Author Share Posted April 4, 2009 No driveaility issues at all. I will try and disconnect the WG today... Link to comment Share on other sites More sharing options...
mickeyd2005 Posted April 4, 2009 Share Posted April 4, 2009 Have you set WGDC = 0 and done a datalog of MRP? Where's the kink in the rpm-MRP plot? Link to comment Share on other sites More sharing options...
praedet Posted April 4, 2009 Author Share Posted April 4, 2009 Well, due to snow and stuff, the testing got delayed. We'll know more tomorrow... Link to comment Share on other sites More sharing options...
2point5GT Posted April 7, 2009 Share Posted April 7, 2009 Sorry, don't mean to steal ur thunder but I have the same problem, except mine started when my battery was dying. The clock kept resetting every start up and the car would struggle to start. Once I changed it, suddenly I couldn't boost more than 13 psi, before that I was boosting about 17 on a TDC stage 2 map. Link to comment Share on other sites More sharing options...
cfdrumr Posted April 7, 2009 Share Posted April 7, 2009 I had the same problem...map says 18psi but m only hitting 12...i just pulled the WG tube and i hit 18..is that boost control? Link to comment Share on other sites More sharing options...
caramall2 Posted April 7, 2009 Share Posted April 7, 2009 That's the method I used to confirm it was some sort of control issue. I had the odd case of one of the shops installing my lines backwards so the pill was in the wrong hose (pill should be in the line coming direct from the turbo housing). If you haven't, read Cobb's good article on the factory boost system: http://www.cobbtuning.com/info/?ID=3482 If for some reason the solenoid isn't bleeding off air like it should (WGDC), then the supply air pressurizes the actuator. As soon as that pressure gets close to the actuator spring pressure, the wastegate starts to open and you loose boost. Stock actuator is around 12 lbs, hence why in some of these problem situations, people get 12 psi of boost but no more. Basically, that's like connecting a hose direct from your turbo to your wastegate actuator with no solenoid. Cfdrumr, if you're still having the issue, have you logged your WGDC? Link to comment Share on other sites More sharing options...
cfdrumr Posted April 7, 2009 Share Posted April 7, 2009 i will today. Link to comment Share on other sites More sharing options...
2point5GT Posted April 8, 2009 Share Posted April 8, 2009 So just to be sure, from the link you posted, line 2 is the one you'd remove to try this right? Link to comment Share on other sites More sharing options...
caramall2 Posted April 8, 2009 Share Posted April 8, 2009 Correct. Again, use caution as boost will go up quick. Link to comment Share on other sites More sharing options...
Spec B Posted April 8, 2009 Share Posted April 8, 2009 Sorry, don't mean to steal ur thunder but I have the same problem, except mine started when my battery was dying. The clock kept resetting every start up and the car would struggle to start. Once I changed it, suddenly I couldn't boost more than 13 psi, before that I was boosting about 17 on a TDC stage 2 map. I think you need to reload your RT Map. TDC tunes require both base and RT, if you are having issues with your battery, you may have erased the RT map. Link to comment Share on other sites More sharing options...
2point5GT Posted April 9, 2009 Share Posted April 9, 2009 I actually tried that, I also tried the Cobb maps both base and rt, reverted back to stock (that sucked) and re loaded both TDC maps. Today, with really nice weather (lo 70s and dry) I almost hit 15. I'm pulling that WG hose tomorow and see what happens. Thanks caramall2 Link to comment Share on other sites More sharing options...
praedet Posted April 9, 2009 Author Share Posted April 9, 2009 Well, w/ changing EVERYthing out, I can get more boost Link to comment Share on other sites More sharing options...
cfdrumr Posted April 15, 2009 Share Posted April 15, 2009 im stuck at 11psi or so...nothing more... Link to comment Share on other sites More sharing options...
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