Crash course in locating boost control/leak/issues?

[TheBlackPearl]

Hey guys,

 

So I've searched pretty diligently and I'm just going deeper into the wabbit hole and hoping someone can point me in the right direction.

[126k on my '05 LGT, 5eat, Cobb OTS stg2, TBE, stock U.P., Stock TMIC and fueling.]

 

This Saturday on my way to work I pulled out of the neighborhood and my wagon felt really sluggish. No CELs, no roughness, just felt like a slug.

I plugged the AP in to check AFR's, knocks, boost, etc.

I was making ZERO boost. Like I couldn't get it out of vacuum.

AFR looked fine(14.6ish), DAM was good at 1.0, and no readable misfires.

 

Drove home (<2 miles) and grabbed wifes and went to work.

 

Get home from work and check the actuator hose and the blue T fitting first thing and they were fine.

I then did a boost check MaxCap's way (by plugging the after MAF/intake tube with a jar, pulling the BOV hose and blasting a regulated shot of air (~15psi) into said hose and listening)

Well I couldn't hear anything. And I'm still not sure if I could 'feel' the air on my lip when i waslooking or not :-(

Noticed some faint oil on bottom of TMIC so made up some soapy water and got to spraying around the TMIC connections and lines but still couldn't see/hear any bubbles :-(

 

I'm lost now so I button everything back up and go for a test drive with the AP plugged in.

It felt more normal-er so I rolled into the throttle a bit and it was making boost.

So I stand on it and it maxes 13.0psi and tapers as it gets closer to redline...

After next corner stand on it again and it maxes 13.0 and tapers closer to redlineblahblahblah.

What the hell?!?!? ZERO boost this AM and now 13.00 twice in a row?!?!?!?

Ahhhhh!

 

I usually see 17.4/.5 as a max and from what I could decypher, thats about a lb high for Cobbs OTS stg2 for my '05 LGT in the first place.

I have hit fuel cut from overboost twice in the past though, but I chalked it up to the cool morning air.

 

What would the likely hood be that it's my BCS being wonky/going bad?

How to test?

 

I'm sorry this is so long winded, but I'm up against the wall here.

I have no effing clue what the next action should be.

 

Somebody, anybody?

 

 

EDIT: I'm gonna re-do the tests/check tomorrow, I was kinda pressed for time earlier so I had to have missed something. Hopefully.

[TheBlackPearl]

Boost leaked checked again and couldn't find any...again.

Went back out to road test and was going to do some logging but it started making a horrible sound.

Like the turbine was rubbing on the housing kind of noise :-(

I pulled up onto my ramps and when I gave it gas to get onto the ramps (putting load on the motor) it made the noise again.

Going to drop the down pipe here in a bit when the exhaust cools and check my turbine.

[TheBlackPearl]

Yep, turbo was the culprit.

Shaft play is minimal, but I can side load it enough to make the turbine stop spinning.

I had the DP down to check shaft play like 4 months ago and it seemed non existent. Granted my feel is not as accurate as a dial indicator, but still.

Well I better start pulling this sucker off and get in touch with BNR supercars I suppose.

 

It'd probably be a good idea to pull the TMIC and check for metal dust, right?

[TheBlackPearl]

Well there wasn't any metal dust/particles in the TMIC so that makes me feel much better at least.

I think I'll just pull the turbo tomorrow after work. I feel like I need a beer.

[Cody480]

Check for flakes in the oil. If theres any in the oil you have bigger problems, if not strap up a new turbo and either a. Clean the banjo filter or b. Recommended remove filter and install separate external filter.

[TheBlackPearl]

I was planning on buying a brand new, uncontaminated oil catch basin so I can sift/examine the oil for chunks. Judging from the look of the TMIC, exhaust turbine and compressor side though, I think I should be good to bolt on a new turbo and b-b-boost.

 

The turbo inlet banjo filter is long gone, but I'm highly positive that the one in the divers side head remains.

[JmP6889928]

Run a magnet through the oil when you drain it. See how much stuff you have. If it's pretty clean, you might be OK.

[TheBlackPearl]

Yeah I plan on sifting the oil with magnets and was thinking of using glass containers so I could potentially see any flecks of contamination.

I want to pull the turbo, drain oil, split open the oil filter, and drop the oil pan to examine them for contamination today.

I never got a CEL/code or any smoke thankfully, so hopefully that will be my saving grace.

[TheBlackPearl]

I got the turbo pulled today and I think it looks promising.

I couldn't see any rubbing on either of the housings, turbines don't show any signs of wear, and the shaft is still intact.

Looks like it was on it's way to puking it's bushings into the motor though.

I could barely measure the shaft deflection with my .0001" graduation dial indicator though, like 5/10ths of a thou. Very suprising thats all it takes to bind.

Zero fore/aft play.

I think I just got really lucky but won't know until I pull the oil pan.

 

Too early to be excited, but I am anyways. I need to be

[TheBlackPearl]

Update:

I sucked a piece of up pipe catalytic converter into the turbo and it created a mechanical turbine blockage.

Got the pieces out and then the shaft play presented itself....Almost enough axial play to touch the housing but it didn't, and about .005" fore/aft play.

Drained oil and thouroughly sifted it for metal/foreign objects. Thankfully there was none! :-)

STI up pipe in hand to replace OEM catted unit with EGT resistor already installed.

 

I'm going against the advice of the shop I talked to and am going to buy a BNR evo16g and IP&T oil line/filter kit. Tuner/shop didn't have nice things to say about BNR turbos and didn't like the upgraded oil line either. I know the shop knows what they are doing, they have an awesome rep and results to match.

The evidence is compelling after reading BOTH bolt on turbo threads (not all 500+ pages, but at least 150-200+) I don't see how BNR isn't the #1 choice for replacement turbos.

This was actually the first time I've heard of a negative BNR supercars review/impression. ?????

 

After these findings, I am "sitting" on the turbo replacement project and daily driving my sbc'd S-10 and saving cash money for the turbo, oil line kit, and GS 2x thick gaskets. Don't want to use CC for this.

 

I was thinking about a dw65c in addition to the above. That would be the extent of my fueling "upgrade" though. Is that even worth it on stock injectors for an added bit of safety?

 

http://i476.photobucket.com/albums/rr126/mikabuc/20130828_155729_zps7f1661ad.jpg

[BoozeRS05]

I've heard some people knock BNR for craming big turbo parts into a small turbo. I don't know much about turbos, but in the 16g range I don't see how it's a problem.

 

Regarding the pump, lots of people upgrade to the dw65c once going with a bigger turbo (vf52 or 16g), even if they aren't going with bigger injectors.

 

 

You might consider some additional preventative maintenance even if you didn't find metal in your oil.. Definately look to inspect/replace/remove the banjo bolt filters, also strongly suggest looking into a new oil pump and oil cooler.