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Discussion Starter · #1 · (Edited)
Basically a self-assembled stg 4 equivalent setup. VF34, UTEC, TMIC, Blitz SBC-iD. BOV is Blitz.

I can't get recent boost creep ironed out! I've had the same setup for about 9 months, except I was using a unichip up until a few weeks ago. I switched to the UTEC, still using the SBC-iD, and the same settings I was using flawlessly with the unichip, now cause overboosting with the UTEC. It just won't hold 18psi. It will from ~3800 to 6000, but then starts building again (3rd gear). I have tried different gain settings and all that...even tried the auto function which works to some degree but boost builds VERY slowly.

I installed/replaced a few things all at the same time (perhaps unwise thing to do) when the UTEC went it:
Changed TXS TMIC from v1 to v2
Changed from unichip to UTEC
Changed from platinum plugs to iridium
Changed from stock airbox to Blitz SUS
Installed oil catch can

I've rechecked almost everything and see no problems. I hear no obvious air leaks under boost. I have run a line straight from turbo nipple to wastegate, and still get creep, except with lower boost. Can a wastegate die?

Just last night I hit boost cut and needless to say if this goes on, I'll probably blow the car up. I know that the UTEC has a great boost control, but I don't have all the pieces to reinstall the oem boost control, so reserve that as a last resort.

If anyone has had similar trouble, please post your fix :) Help!

(this is a mirror of a thread I started on nasioc...looking for answers people! those who frequent both boards can ignore one of these :p)
 

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What downpipe are you running? There have been cases where the downpipe design restricts the wastegate flow so much that it's actually more efficient for the exhaust gasses to flow through the turbine. This pretty much eliminates any control you have over your boost. You might have to switch to a different DP....
 

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I think that his setup worked fine before he made his last round of changes - which didn't include a DP change.

These are the things he changed:
Changed TXS TMIC from v1 to v2
Changed from unichip to UTEC
Changed from platinum plugs to iridium
Changed from stock airbox to Blitz SUS
Installed oil catch can
Now he has boost creep - same exhaust.

Weird - keep us posted!

P.S. Good thought on the DP though DJ! Interesting findings regarding DP design, eh?
 

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Discussion Starter · #5 ·
Yes, no creeping until recently (last two weeks or so)...I've had the same exhaust for a long time!

I'm trying to hunt down a replacement wastegate to try. Not sure how easy it will be for a VF34 :rolleyes:
 

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Even with those changes, it could still be the downpipe design. If the UTEC timing maps are retarded even a few degrees as compared to the unichip it could be sending enough combustion energy to the turbo to overwhelm the wastegate. I've heard of this happening with a VF23 which has a larger exhaust housing than a VF34. I've only seen it happen with a flat-flange downpipe though, thus, my question as to which downpipe you are running.

The easiest way to check the wastegate would be to reach in and try to move the actuator arm by hand. You could also unbolt the downpipe and hook a bike pump to the actuator and see if you can get the wastegate to move.

I have a feeling it isn't a malfunctioning wastegate though, as you would be seeing elevated boost levels well before the 6000 rpm you reported. The fact that you can maintain boost until 6000 and then it starts creeping is what led me to think it was an exhaust issue. That is to say, at around 6000 rpm, there is simply too much energy for the wastegate to release.
 

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Discussion Starter · #8 ·
I need to correct the 6000 remark, it happens before that perhaps as early as 5000.

I can move the actuator arm by hand.

So I could correct this via UTEC?
 

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Are you running closed loop or open loop boost control? Either way you can try to lower the FBC duty cycle (or the CLB "values") to try and taper the boost off in your problem areas.
 

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Discussion Starter · #10 ·
Running an SBC-iD. Same results with a hose direct from turbo nipple to wastegate. Should only get 9psi ... keeps rising! Control is completely mechanical at this point.
 

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Doh. I'm a dork! Shoudl have read closer. VERY weird. Not sure what the difference could be if you are running the same exhaust, and same boost control device.

Have you been logging the boost creep? Any chance you could post those logs that show the boost climbing?
 

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I have spent the better part of my life troubleshooting. Rule number 1, if at all possible, return to the original configuration, then work your way back until the problem presents itself again.

In this case, I would start by re-installing the unichip, if you still have it.

I wouldn't suspect your other mods, unless you possibly disturbed something when swapping out the TMIC.

Also, carefully check all of your hoses which make-up the boost control loop. If you have a small tear or loose connection, it could present itself at higher pressure, but not lower, IE: >5000 RPM = >boost pressure.

Don't overlook the small things (hoses/connections). It's not always a big problem causing your big problem.

Just some thoughts.

Good luck. Let us know what you find.

Curtis
 

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Lastly don't overlook a malfunctioning actuator. Although rare it is possible. It has happenned once with a VF34 although conversely it has never happenned with a PE turbo with the same combination of mods so I know it's not the downpipe or flow capacity of the rest of the system.
 

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Si2WRX said:
Basically a self-assembled stg 4 equivalent setup. VF34, UTEC, TMIC, Blitz SBC-iD. BOV is Blitz.

I can't get recent boost creep ironed out! I've had the same setup for about 9 months, except I was using a unichip up until a few weeks ago. I switched to the UTEC, still using the SBC-iD, and the same settings I was using flawlessly with the unichip, now cause overboosting with the UTEC. It just won't hold 18psi. It will from ~3800 to 6000, but then starts building again (3rd gear). I have tried different gain settings and all that...even tried the auto function which works to some degree but boost builds VERY slowly.

I installed/replaced a few things all at the same time (perhaps unwise thing to do) when the UTEC went it:
Changed TXS TMIC from v1 to v2
Changed from unichip to UTEC
Changed from platinum plugs to iridium
Changed from stock airbox to Blitz SUS
Installed oil catch can

I've rechecked almost everything and see no problems. I hear no obvious air leaks under boost. I have run a line straight from turbo nipple to wastegate, and still get creep, except with lower boost. Can a wastegate die?

Just last night I hit boost cut and needless to say if this goes on, I'll probably blow the car up. I know that the UTEC has a great boost control, but I don't have all the pieces to reinstall the oem boost control, so reserve that as a last resort.

If anyone has had similar trouble, please post your fix :) Help!

(this is a mirror of a thread I started on nasioc...looking for answers people! those who frequent both boards can ignore one of these :p)
hey erik whats up i saw you run that 12.73 last year at the nopi fast and furious i am the guy with the white wrx. i also saw you beat the supercharged bmw m3! good to see ya buddy!
 

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hey

hey there,
seems like everyone is having tuning problems with their utec, well not everyone but ya know. There are many things to consider when diagnosing your problem. First of all, you never mentioned if you have new injectors or a fuel pump,. That would be a problem, not that it would make your boost rise to high. What's an sbcid, if you use it to adjust your boost, that could be the problem.

also, have you checked your boost on a laptop yet? I have noticed that 15psi on my gauge is totally different than 15psi on my utec. I think the utec is more accurate than the gauge. Also, if you didn't change your boost map, then you are running open loop boost control. That means your boost isn't as exact as if you were running close boost. With close boost map has numbers that equate to a certain pressure(not psi, but if you put in say 50, at that point on the map you will always have the same boost if you drive right). This means you can make more precice measurements than with an open loop, and it will help make a more efficient map which results in a faster car. With open boost the nubers on the map represent a duty cycle on the boost actuator, which means that you will have different spikes on the map at certain boosts and your boost won't be as high as long, and will come up a lot choppier. I have been talkin about this in a few posts, and I am not experienced enough to change my own open loop map to a closed loop one even though I want to. I'm scared of screwin up my car.

anyways, like I said b4 I think the problem is mostly your boost gauge if not a technical problem. If it is a technical problem...it's all in your maps.

on another note, if you think that it's overboosting because the cel flashes, it is definately your maps(if you use an unmodified stage 4 map)! I have the same setup as you, and I had that problem when I pushed it and got to about 5200 rpm. Every time at that exact rpm. If you have the exact same problem, e-mail me at [email protected] and I will send you my fixed map(I use a stage 4 but with one part fixed at 5200rpm). If your car doesn't have that problem at 5200rpm then I dunno. But the cel means that you have a knock and need to change the timing at that point in your map.

I have been typing about this a lot lately cause I am really interested in changing my maps. I think that the base maps from turbo xs are good starting points(if you wanna use an open loop boost setup), but they are not efficient at all. anyways like I said b4, I basically have the same setup as you, so if you want a newer map when I make one, it's all yours

peace

ps- I also noticed that on the stock turbo, you can't open the wastegate easily by hand, but on my vf34 it is easy. I really don't think that is the problem! I think it is easy to move because it has to be able to move quickly to work well.
 

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Discussion Starter · #16 · (Edited)
Re: hey

I do have injectors and fuel pump. Also, the Utec wasn't the cause of my creep.

I have checked my boost on a laptop. The Utec MAP was not calibrated well for me. First problem was it didn't read 0psi with the car off. It read 1.2psi low all the time. After calibrating it's now great. I have a boost gauge, Blitz boost controller, and Utec that can indicate boost. After dynoing my car, the dyno indicated boost of 18.3psi... Blitz SBC-iD showed 18.5psi. Utec 18.3psi. Didn't check the gauge. NOW my Utec indicates proper boost, but by default it did not.

My boost is controlled by the Blitz SBC-iD. So the Utec isn't in control of boost at all on my car. Has nothing to do with the maps.

After tooling around with the car a lot, the boost creep is directly related to the test pipe. If I run the cat pipe, there is no creep. That's how I currently have the car setup.

I'm not exactly sure why it creeps with the test pipe... perhaps too little back pressure?

kelwrx > Thanks! That BMW was extremely nice.
 

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So it sounds like you just needed more backpressure across the turbine to make it easier for the exhaust gasses to flow through the wastegate. I'm still curious which downpipe/exhaust you're running.
 

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hey

it sounds to me like you are doing some serious overkill. THERE IS NO REASON TO USE THE BLITZ BOOST CONTROL AND THE UTEC. I THINK THAT IS DEFINATELY YHE PROBLEM. If I were you, I'd take out the blitz boost controller. that's about it. peace,

hippy

the problem isn't your wastegate, it's your boost controller, take it off.....
 

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Discussion Starter · #19 · (Edited)
Blitz are proven to be excellent boost controllers. The VF34 is known to creep. I know that the UTEC can control boost just fine. I've had the Blitz on my car for about 16 months now. Was running it with a unichip before I got the utec 3 months ago. I decided to stick with the Blitz to allow minor boost tweaks easily and quickly without needing the laptop.

The test pipe is the problem. I run the cat pipe currently and there is no problem. The exhaust gas takes the path of least resistance... with the test pipe in place, the exhaust flows too well. The ball-bearing VF34 spins too well. This causes the gases to continue through the turbo exhaust wheel instead of out the wastegate like it should at full boost. This allows ~1.5psi of creep after about 5k rpm. I have also run wastegate boost and an MBC in an attempt to troubleshoot. It doesn't matter what's controlling the boost...it'll all creep.

The only fix I know of for this scenario is to mildly port the wastegate.

Details on my setup are here: http://www.thinkturbo.com/wrx.html
 

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hey

like I said b4, THERE IS NO REASON TO HAVE TWO BOOST CONTROLERS ON YOUR CAR, AND THAT IS WHAT YOU HAVE. I WOULD TAKE ONE OFF IF I WERE YOUthe blitz one cause if you took the utec off your car would go slower, but it might go faster withought the blitz!)! I DON"T KNOW WHY YOU WOULD WANT ANOTHER BOOST CONTROLLER OTHER THAN THE UTEC! IT MAKES NO SENCE!.

THE PROBLEM IS NOT WITH YOUR TURBO!!!!!!!!!!


peace

ps-why do people ask for help if they won't take any?
 
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