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My Unassuming RBP LGT Journal/Tuning Thread


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  • 2 weeks later...
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  • 3 weeks later...
And it appears I was. Got the replacement o2 sensor in and I installed it. I was a bit discouraged at first, because while the surging was drastically reduced and barely noticeable, the rpms still dipped and sometimes stalled the engine like before. I brought the car home and thought about it for awhile, then I remembered something; The ECU learns. I went back out with the car and as it turns out, the stalling issue was no more. I'm going to take it out again to guage the surging, but I'm confident that whatever surging there is, the ECU may take care of it, or we can tune it out since it is so minimal.

 

 

Okay, I am now at a total loss. My car has been driving fine until just the other day. I was leaving work and tried to start the car. The power blipped and then no power from the battery. Waited a few more seconds and then the battery had power again and the car started (later traced that back to a loose positive terminal which I corrected). However, it was AGAIN experiencing the EXACT same symptoms from before I changed the upstream O2 sensor (explained in post 46 above). I replaced the o2 sensor again and the issues continue.

 

What's puzzling is that the car was fine until the battery inadvertently disconnected and reset the ECU. The tuner said that it would reset automatically to the map that it was already running. My assumption was that over past month, the 02 sensor went bad, but the ECU hadn't learned that until the reset. Well it sounds preposterous and apparently it is since the new sensor is doing nothing to alleviate these symptoms now. I've tried disconnecting the battery and resetting via romraider to no avail. I didn't start a new thread since all the information I can give is in this thread already. Can anyone give any insight into what is going on?

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I know it really shouldn't be the tune, but I'd still be curious if any non-standard tables have been modified. I'd really like to see a current to stock rom comparison using SimpleTune. It will tell you exactly which tables have been modified.
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Strangely enough, just a couple days ago, things started to alleviate and running smoother. Then yesterday, all is well and I cannot reproduce the symptoms. Took a bit of driving to learn. I'll post a learning view today.
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Yea, not happy at all. How confident are you with the MAF and injector scaling and injector latencies? If very, then find your leak! Of course you know, but stay out of wot too. Are you running e85?

 

Oh, and get the new LearningView.

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Not very confident especially since that was all supposed to have been dialed in already. However, with the issues we have been having, I'm thinking that we'll have to start over and the fact that's it has been so long, that I don't know what has been changed.
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Are you still on 91 and not e85? I'd say swap back the OEM intake (gotta love the RacerX for this), make sure there are no leaks, flash stock MAF scaling and wastegate boost, and then make sure the injectors are dialed in.

 

I can help you with all of this if you want or can't time with Mark/tank.

 

From there, we swap back your intake, dial in your MAF scaling, and send you off for tuning.

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  • 2 months later...

Who wants to shoot me now?

 

This project is slowly but surely losing it's enjoyment.

 

Let me recap the last couple months. Tuner has been working on maf scaling and when he was finally ready to turn up the boost, my "clunk" kept getting in the way and the knock sensor kept picking it up. Needless to say, can't tune when false knock is causing FBKC. That turned out to be a chewed up tranny mount. I changed that out to the group n and the clunk was gone. On a sidenote, I also added in the Agency Power pitch stop mount. Those 2 pieces added in with the Group N motor mounts already installed really tightened things up and I'd recommend these upgrades to anyone Stg2 and beyond. I should have done it long ago.

 

Back to the here and now. My tuner gets the car back and touches up the Maf scaling even better and as he begins turning up the boost, he hits a brick wall at 14-15psi. Since I'm running hybrid boost control, we think that maybe one of the boost controllers has failed so I test each one out by running it solo with no different results. Still can't get past 14-15psi. Mind you, boost leaks were already eliminated as a cause so it must be some other mechanical error. What's next? Possibly the wastegate actuator? My subaru mechanic buddy suggests I bypass the boost controllers and run straight wastegate to see what happens. I hit 7 lbs of boost using that method. That sounds about right.....except I'm running a 15psi wastegate actuator. Could this really be the problem? What are the chances that the actuator would go out? :spin:

 

I will say that other than not being able to get past low boost levels, the car is running terrific. As a daily driver it's very smooth, and it runs like a lamb. Even at only 14-15psi, still sling shots you once you hit 4k rpm.

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Definitely sounds like you're stuck on wastegate boost.

 

My guess is that there's a problem with the boost controller setup, maybe both are bad? I'm picking up a GS MBC today. We can hook that up on yours to see if we can get above 15. You could also have a boost leak that only opens around 15psi. A boost leak would mess with your MAF, causing your tuner to have to work it over. When was the last time you went over your FMIC pipes? I just found mine were leaking a bit around the BPV because the bolts had stripped out. My car runs a lot smoother with new BPV bolts.

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Make sure that actuator is in fact set to 15lbs (AVO actuator)

 

Mine on my AVO380 was not. You adjust it by adjusting the rod.

 

Get it working with the actuator at 15lbs first then go from there.

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Definitely sounds like you're stuck on wastegate boost.

 

My guess is that there's a problem with the boost controller setup, maybe both are bad? I'm picking up a GS MBC today. We can hook that up on yours to see if we can get above 15. You could also have a boost leak that only opens around 15psi. A boost leak would mess with your MAF, causing your tuner to have to work it over. When was the last time you went over your FMIC pipes? I just found mine were leaking a bit around the BPV because the bolts had stripped out. My car runs a lot smoother with new BPV bolts.

 

I'm going to swap in my stock bpv just to eliminate that possibility, but my bolts are in good condition. Logs don't act like a boost leak, but more an issue with boost control, but I will double check...well, triple check. :spin:

Make sure that actuator is in fact set to 15lbs (AVO actuator)

 

Mine on my AVO380 was not. You adjust it by adjusting the rod.

 

Get it working with the actuator at 15lbs first then go from there.

 

Greg, are you talking about setting to proper preload. That's something I can try, but if there's another type of adjustment, let me know.

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Yea I think you adjust the rod, and put a vacuum on the actuator so it opens at 15lbs.

I would think a mightyvac or something would be a good tool to use to check it.

 

Mine was waaaay off when I had Cobb check it before my tune.

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  • 2 weeks later...
  • 1 month later...

Thought I'd start updating this thread as I've actually forgotten about it. :redface:

 

Have had numerous issues in the process of getting this thing tuned. Nothing has been majorly wrong to where it has cost me obscene amounts of money, just annoyances along the way.

 

I can't even remember everything and I probably should have kept it journaled here for my own benefit. Let's see. I already mentioned the tranny mount.

 

We suspected an issue with the actuator, but now I'm betting there was nothing wrong with it. However, In the process, I decided to switch to an EWG setup instead of changing the actuator. I went with the coated grimmspeed 44mm ewg uppipe mated to the tial 44mm gate. That was fun to do. The first uppipe sent to me didn't mate to the turbo. That's right, it didn't fit. I took it to the local subie speed shop to verify I wasn't a dumbass and sure enough, it would not mate to the turbine housings they ha laying around there, either. Luckily, they had a coated GS pipe waiting to be installed on another car that I just grabbed from them. I contacted the vendor and grimmspeed acknowledged that this has happened a few times and sent me another pipe, no questions asked. They sent along with that a shipping return label for the faulty pipe. Apparently, when it was tapped for the studs, a couple holes were just a few degrees off so the studs went in cockeyed. This was very hard to pick out with the naked eye. Anyway, grimmspeed sent a coated pipe when I originally bought it uncoated because I explained to them that I had to reimburse the speed shop for the one I grabbed from them. On a side not, I'm using Cobb's new iwg bracket to keep the iwg sealed. Nice piece and very easy to install and adjust.

 

As I was working on switching to ewg, I noticed that my passenger side fmic pipe was dented pretty bad from bottoming out too many times, I guess. I contacted Bryan (itsme) for a replacement and he sent one promptly for a meager fee. When it arrived, I replaced it and I found the source of many of the problems we've been having with this thing.

 

http://i108.photobucket.com/albums/n29/joeleodee/IMAG0374.jpg

 

Yeah, that's going to cause some problems! :eek: We think it started as a pinhole leak that was not noticeable and progressed to this state over time. This thing built boost horribly and hit a brick wall in the 15-16 psi range with wgdc above 80%.

 

After this, I got it back to the tuner and he had to rescale the maf and injectors along with adjustments for open and closed loop. I recently got the car back from him and it is a different machine altogether. He has not added boost nor tuned for power, yet, but it runs amazing at only 13-14 psi peak. There is no more surging under light load and the throttle response is.....responsive. Whoda thunk? :rolleyes: It will hit peak boost by about 3900 rpm whereas before it wouldn't hit peak until about 5100 rpm. I'm betting once this thing is turned up and fine tuned for power, it will hit at least a couple hundred rpm earlier which is not bad for a big turbo like this. It is a different car completely without that big gash in the pipe.

 

As it sits now, the other day I popped a p0172 'too rich' code. I cleaned the maf and reset only have it pop again a couple days later. Then I took the air filter out to clean, reset it and it hasn't shown again. However, I took a couple logs and noticed that now it is running dangerously lean and causing it to knock. My tuner thinks there is some vacuum leak somewhere. I haven't been able to find a vacuum leak from the usual suspects, but who knows. He's supposed to get it back next week to take a look. In the meantime, can anyone comment on other possible issues? I just thought that now that the air filter is clean, it's getting more air and not enough fuel to compensate since nothing else changed. I'll post some before and after logs.

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Car: 2007 subaru legacy spec b

Tuner: innovative

Transmission: 6speed

Peak Horse Power at RPM: 400

Peak Torque at RPM: 400

Fuel: 94 50/50 water meth

Engine/Power Modifications: avo500, avo fmic, id1000

Driveline Modifications: act hdss

Suspension Modifications: avo rear sway, swift springs

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