--PROBLEM IS FIXED, SEE MY LAST POST. THANKS TO SCOTT AT SOG! :bowdown: Hey everyone, I just found this site and I hope to make a trip to Atlanta to check out the club before I head to Korea for the next few years. I am in the Army and I just got back from Iraq and I am looking to do some more stuff on my car before I head out...only I have a slight problem I need fixed. Here is the layout of my car, I have done quite a lot to it and some really great friends in the Pac Northwest helped me with them: 2004 STi (US) Pearl Blue Engine/Exhaust: GT Spec-II header and up-pipe Turbo Xs 4in Down-pipe Full HKS Carbon-ti Exhaust (no Cats now) Turbo Xs RFL BOV (with all shims installed) Stainless Steel Short Ram intake Others: Tenabe Springs Front/Rear sway/strut braces Under Carriage Brace Anyways, the issue I am running into now is that when I accelerate to about 100mph in 5th gear, and EXACTLY at 5500 RPM (everytime, done it 8 times now, tested it on an open strecth of highway), my car seems like it just hits the "governer" because my BOV kicks in and blows out, and the car studders suddenly and I have to shift to 6th to keep accelerating (which is slow from 100). I still have 1500RPM til the factory redline, so I don't get it. I am in Columbus GA and there are no tuner shops here, so bear that in mind. I have all the necessary tools/lifts etc to do the work needed, but what I am thinking is that I might need to send my ECU off over-night to get reflashed because of the mods I made. Let me know what any of you think and if you have run into this type of problem too. Also, I am looking for the thread about meetings/dates/locations so I can make a trip up to Atlanta. I need to go get some more Redline oils for my rear-diff and tranny anyways! Hope to talk/see you all soon! sti_lish
sounds like boost creep, or a fuel cut, to me. I got it several times before i was tuned after adding my tbe. the good news is some sort of enginemanagement will likely fix this problem, bad news is prepare to spend $600-$900 getting it done. I personally have Ecutek EM and love it.
get rid of the BOV and intake. then get some EM. that should cure most of your driveability problems. See Scott at SOG for an EcuTek re-flash.
yeah, i agree on getting rid of the BOV and intake. Take it to Doug @ Topspeed and get either Protune or Ecutek. -- Brian
+1 for EM, tuning the car should fix your problem. I would go to SOG and let Scott Road Tune your car. Will be able to diagnos your issue better on the road than on the Dyno. If you do go to Topspeed, maybe have Doug Road Tune a little to see what the problem is, but like Rolling Trip said, sounds like Fuel Cut.
Do you have a boost gauge? Does it do it at the same point in different temperatures? It definitely sounds like a boost cut. Removing the BOV and short ram (hot air intake) will improve your performance. If you come up this way I'd be happy to datalog your car and let you know exactly what the problem is. Then we can discuss solutions. SS
5th Gear I agree with everyone about it. I think it is most likely a full cut out or something with the BOV (most likely). I think I will take the BOV off and put the factory OEM back on and try that out to see what happens. Before I do that I will check it out on the highway again, try to get a good shot at all my gauges with a camera so I can reveiw it all. I have the OEM installed Boost Gauge and OEM dash so I can fit them in the same picture. I think I would probably be better off with the OEM BOV or a Greddy one that puts some back into the system and doesn't release it all. I also noticed that I get an engine light when it happens, will have to write that OBD-II code down too (yes, I actually carry a reader). I am used to getting O2 sensor codes because of the lack of catalysts. I have my O2 sensor recessed a bit so it doesn't come on all the time but it tends to happen often at high RPMs when the air shoots through faster and hits the sensor. Maybe someone has a better idea on how to fix this issue too. I am coming up to the install get together on 28 Jan. Will see if I still have the problem then. :sx: Thanks for all the ideas. I will try the BOV and I just got a BLITZ SUS Power air cleaner, think I will put that on right after the test too. That might help reduce airflow restriction. I need to get a good piece of heat reflector (like the one around the Turbo) to put around the intake so it doesn't suck in heated air off the engine...any ideas on that one? All in all I know I need a reflash and a possible tune job. Just can't afford to have my car gone from here because I use it everyday. Maybe I can get it done in Atlanta on the weekend up there at the shop you guys mentioned or during my upcoming MONTH OFF! Steve
I don't think the BOV is causing your boost cut, but it does hurt post-shift performance, so it would perform better with the stocker. What is your boost gauge doing when it hits the cut? If it's running over 1.2 mpa then it's definitely boost cut. I do *NOT* like the Blitz intake. These cars are VERY sensitive to intake sizing andI have seen ugly things from that one. we can tune for it, but that is NOT my suggestion. The engine bay gets up OVER 185 degrees during the summer a cold air is MUCH better, even stock air box is MUCH better. We can tune it in just a few hours. Sell your short ram and your blitz and either stay with stock or get an Injen or APS CAI. SS
Fixed it, thanks much to Scott Everyone, I just fixed it and tested it and works correctly again. I am still going to get an ECU-Tek, Tune, and a different intake. I took the Blitz SUS intake off and the Turbo Xs RFL BOV off, disconnected the battery, and put the OEM parts back on. Then I reconnected the battery, and let the car idle for 10 minutes, then took it out on a clear stretch of I-185. After cruising for 20 minutes up and down the same 8 miles (and checking for the "man"), I let it rip. It went just fine to 7000RPM in all gears (minus 6th) and did not cut-out (I got it to 130mph). Not really a long enough stretch to get faster and traffic started to come so I stopped while I was ahead. Anyways, thanks much to Scott at SOG. I will be visiting him soon. Just miss that pssst noise now...but if that means cut-out, screw that. Steve
if you cant live without the bov, you may want to consider a 50/50 BOV, just make sure you get tuned with it ON, and dont add it later unless you plan on getting it retuned. personally i had a hks 100% bov and traded it for a gfb 50/50 that sounds really good. but performance wise they do nothing, until you go big turbo.