Hi all. Very, VERY stumped on a current problem with my baby, a 2010 SS with LSD and an RPD. 1st, what happened...

Trifecta budget tune downloaded and installed say, a month ago give or take. "WOW MOAR BOOSTZ WOW" was my initial reaction, as my car is bone stock and this plug-and-play tune was a lot of fun. No Lift Shift is wonky with the tune tho, works PERFECT on stock tune but wouldn't work all the time with the tune activated via 'select-a-tune' feature.

I'M ALSO AN IDIOT, and put 6qts of oil in last oil change, I blame having an LSJ for 4 years. THIS, in combination with massive misfiring during NLS attempts, I had a ton of fuel in my oil. I emptied it to find 7+ quarts of fluid in my drain pan, ughhh. I must have had a TON of blowby under super high boost as well as all that oil/gas blowing out both the PCV AND the vent, both pre-turbo. Didn't know about any of that until...

I was driving thinking, wow I'm getting used to the power... Nope, car was loosing boost. A few 40-100 runs later, I go into what I now know is mechanical boost. Weird. Threw a code, used my scanner that I keep with me 24/7. Pulled over, P0299. Turned on and off, cleared code, checked my RPD boost guage... only hitting 19PSI tune on and 14PSI tune off, OK that's less than the 23/15 I was seeing. Later in the day, 17 and 12. Then 14/11. By 3 to 4 days after I first had the issue, 7PSI tops either way.

After scratching my head a lot, pulled the downpipe to see my 1st cat with a giant hole in it and debris logged in where the O2 bung restriction is. Smashed out cat, popped pipe back on, was hoping for the best but I'm still at 12PSI tune off and 13PSI tune on. Better, but no where near where it was.

Threw P0299 about 30+ times in the last 2 weeks, naturally. Threw a P0101 code once. Things I've checked in addition to the downpipe:

• Idled, listened for whistles or vacuum leaks, maybe hear one near the intake mani but I'm pretty sure it's a noise I've heard before.
• Searched the forums, found the boost leak test and made a jig. Pressurized intercooler piping off turbo to 28PSI, no leaks heard and rubber couplings feel tight. Wiggled pipping, shook intercooler, tried flexxing it etc. etc., no leaks heard or seen.
• Cleaned the MAF as per my P0101. that code hasn't returned.
• Also cleaned both the lower charge MAP and intake mani MAP.
• Checked for shaft play. There is inward and outward by a tiny tiny amount, maybe less than a mm, and same for up and down... tiiiiiiiny bit of vertical shaft play even less than inward and outward. I don't see any scoring of the compressor housing nor do I hear it scraping.
• As per a TSB, checked wastegate actuator solenoid nipple, no cracks. Pulled it off turbo and bench tested, it clicks and seals 100%. 3 vac lines on it seems fine.
• Seafoamed the car. A lot of smoke. Standard sized can, I put the 1/3 in oil, 1/3 in a near-empty tank of gas, 1/3 in intake at the mani right where it goes down to the vacuum tank. Did another one, 1/2 oil 1/2 intake mani, a TON of smoke wow, way more than my old LSJ when it was running poorly.
• Checked intercooler POS oil catch thingy on the bottom of stock intercooler, seal looks good.
• Checked all vacuum lines, everything seems fine. I removed both ends of all the lines and sucked on them, no issues tho I didn't expect there to be.
• BPV stays in under vacuum, removing vacuum and it pops out like it should. Looks in good shape.

I did wire my wastegate shut when I was first hitting mech. boost thinking my wastegate actuator diaphragm was torn and it wasn't playing nice with the solenoid, no change. I removed the wire after I saw the cat exploded thinking "this is got to be it so I'll take the wire off" perhaps I should re-wire it shut to rule out solenoid or actuator failure?

Also, things I'm thinking it could be... or scared it could be;

• Cracked exhaust mani?! Saw a Sky have one, it's entirely possible with the amount of fuel that flew through exhaust...
• Bad turbo? As I mentioned there is a microscopic amount of shaft play.
• Backfiring, chunks of cat flying back and hitting turbine, is that possible?
• Coked up valves so bad one is not sealing right?? I should do a leak down test...
• Wastegate actually needs adjustment? She spools to 6 or 7PSI with normal speed as if there's no problem, from 7-11ish, you can tell the turbo is hesitant.
• An intake boost leak that I can't find to save my life?!?
• Clogged exhaust? Perhaps the 2nd cat is restricted too? Going to pull the DP and run open exhaust see if that helps.
• BPV leaking? do they leak under high boost, causing low boost like this?
• BPV solenoid? It it leaks, the boost signal might not reach the BPV and cause it to not seal?

I am OK with driving the car as is right now, it still boosts 10PSI no problem and I just can't push it hard or it will mech. boost and then be slow as hell. Oil was of course changed and the oil is super clean, no smell of fuel detected and it is at the right level. SO stumped as to what to do next. I am capable of doing all of my own work, never did a turbo swap but I have air tools and persistance heh.

Going to try in order;

• Going to run a leakdown test tomorrow, got a gift cert. to harbor freight so I can get a tester. Low boost and a ton of intake/head gunk scares me tbh.
• Seafoam car again at PVC pipe inlet, let it go through turbo, intercooler piping, TB, intake mani and head, etc...
• Pull DP and run open exhaust to rule out downstream restrictions.
• Wire wastegate closed to rule out solenoid/actuator BS.
• Clean throttle body, no I didn't do this yet but it just occurred to me as I typed. P0299 code when thrown shows freeze frame data of TP% at 100% though?
• Pull intercooler piping and intercooler, clean intercooler, can they get gummed up or clogged??

Any other suggestions from the cobalt gods? Sorry for super post but I'd rather do one big post than ask ALL of these questions over the last few weeks. I use the search button

 

Boost leak. or BPV isn't staying shut.

 

The NLS feature shouldn't be used when your tune is on, that's why it doesn't work right.

 

Yeah Don't nls when your anything but stock tune. Your asking for trouble if you do.

I'm wondering if you overfilling the oil didn't wreck some sensors.
Do you have stock map sensors or gms1 sensors?

I would perhaps start there.

What mods besides the tune do you have?

 

Going to look again for leaks but I'm confident my hot pipe, IC and cold pipe are OK. BPV leaking... How can I check that? Can I run a vac tube right from the cold pipe nipple directly to the BPV so as to make sure it is getting boost to keep it closed, vs relying on that BPV solenoid which I haven't bench tested yet? OR, I can get a forge BPV but I'd rather not by it for $150 unless I was sure it was leaking. Spring does feel flimsy as hell, surprised it holds any boost.

I now know never to NLS tuned! When it worked wow the way the torque can in was awesome, and the NLS feature was a part of the tune for Sky and Soltice folks, so I figured it was well put together and would work fine. Lesson learned. I got lazy NLS'ing anyways.

As for some the oil overfil, yea it was bad. Between the extra quart, fuel in the oil etc., it was over by a lot. I'm thinking excessive blowby gunked up a lot of stuff.

I'd love to drop some $$ and get a new BPV, upper and lower MAPs and see what goes on but I'd rather not throw money at it. ZERO MODS besides the tune, completely stock... original 2.5 Bar sensors. except for the downpipe, which is -1 cat pre-O2 (#2) sine it kind of doesn't exist anymore

Thanks all for quick replies! Are the things I want to try a good place to start? what would be hilarious is if I had a portable air compressor with a 1 Gallon tank on my passenger seat and had it set at say 30PSI and run that to my BPV to hold it shut? I think outside the box heh. I also fill my car now to the proper level too...

 

I'm still not sold on the bpv being the problem.

The fact that that the tune on tune off boost levels are so linear makes me think it's the ecu restricting the boost due to it seeing peramiters it doesn't like.

If then bpv were sticking I would expect your boost levels on tune and off tune to fluctuate more.

 

I don't have much in the line of suggestions other than don't buy a harbor freight leakdown tester. They're garbage. I bought one and it was so inconsistent that it would tell me 15% leakdown on one cylinder, move to the next and get 45%, move back to the first and get 35%. I could never get the same reading twice even with less than a minute between tests

 

K, no harbor freight tester. I might order 2x map sensors online and pop em in one at a time to see if anything changes. Otherwise I have no idea what else to try next.

Can our stock intercoolers get clogged?? Also, the white smoke at idle is gone come to think of it, ever since I changed the oil... Perhaps it was just the residual blowby that was being burnt? Any1 got a hook up for where to et both sensors for cheap? CED, RockAuto?

 

I work overnights at a hospital and get to drive to work with no1 on the road. I did a few 40-60 tests in 3rd, I can hit 10PSI tune off and 12 tune on. 10 is 2/3 of my normal 15 @ NY summer & sea level, but 12 is about half of the 22 I saw when the car was working.

Is it possible for a sensor to fail and register incorrect data without throwing a code? I was hoping the sensor could burn out completely so I'd know exactly what to do...

 

The sensors themselves are actually pretty cheap, just need the part number and you can find them anywhere because they're made by bosch not gm. Its the pigtails that make it expensive. I bought mine from ZZP

Edit: I just assumed you were talking about the 3 bar maps but if you are talking about stock, ignore the part about the pig tail lol

 

Went to seafoam my car again because last time I did, I swore I had some smoke coming out my engine compartment by the rear... What can we make of this? Exhaust manifold crack? Bad gasket? It's not leaking from the flanges.

Video here https://db.tt/orIwB1xt

 

Seafoam doesn't accomplish allot with direct injection.

Your cats could definitely be clogged specially with all the oil that likely ran through your system.

Maybe your turbo did bite the big one....
I would expect over boosting with clogged cats
Unless they are so clogged they won't even let the turbo spin.

 

I blew a hole in one cat, I removed it already. Exhaust restrictions lower boost for turbos, they raise boost for superchargers.

Yea I read the same about seafoam and DI, couldn't hurt to do it. I might have time this weekend to work on the car I hope. I'd like to run it with the DP out to eliminate exhaust restrictions as a culprit but what about that smoke coming out the manifold? I'm pretty sure it's cracked, any1 else think so?

 

even then....

 

Not for nothing but Chevy did a great job on the NLS. It's not about being lazy or being unable to do release the gas and do a quick shift, the way the ignition and timing and boost all come together works well.

I would NLS 1->2 and chirp the wheels perfectly every time, torque management for NLS would bring on the power into next gear in a way that really let's you feel the power. A good 1->2 shift without NLS requires traction control to be off so it wouldn't bog. Same for 2->3, great NLS but without it sometimes the car would bog. Yes I know how to shift, been powershifting my dad's C7 stingray and had years of LSJ speed shifting under my belt.

So when this budget tune from trifecta states it has NLS support, I expected it to work. Too bad it probably didn't work not because it wasn't tuned right, but because of massive blowby causing misfires.

As per my previous post, gonna rip out everything from the exhaust manifold and downstream to see what the deal is. I wish I knew of a turbo cobalt on LI that wouldn't mind swapping MAP sensors for a short ride...

 

Turbo is shot. Ton of play both laterally and radially. New turbo ordered. Going to make sure intercooler isn't clogged and pretty much mint out the car prior to install.

 

https://db.tt/6Jsw06OZ

 

Lol. That's you're problem for sure.

 

Any1 able to tell me why I had visible exhaust by the turbo/manifold area in post #11? I thought I was just going to have a cracked manifold or bad gaskets but the gaskets look great, no signs of leaks and no carbon trails and the manifold is crack-free.

A new turbo was necessary due to all that shaft play in post #17 but I'll just have to put everything back together and see what happens I guess!

 

Buuuump... need some serious help

Ok so, pulled the turbo and as you can see in post #17, lots of shaft play. I bought a K04R from a forum member and popped it in with my original wastegate solenoid and actuator I swapped over. I'm not underboosting on stock tune anymore, sticking around 14PSI at WOT on stock tune instead of the pre-turbo swap 11PSI, though I attribute the extra boost is due to the larger compressor wheel, I believe my original 'underboost' issue still remains.

With my RPD gauge, I usually keep it on engine/torque and when she was runing right I'd always be between 255-265 torque consistently from 2300 RPMs and up to 5ish before I took my eyes off it. Currently, she takes forever to get to 230 torque and feels sluggish, I have the same problem pre-turbo swap just now I have a bit more power from the upgrade, but only enough to fill the gap and bring me back to stock levels, there's still something going on.

New sounds... the turbo 'whoosh' during spool is ultra loud, also my BPV is occasionally making a hooting noise on release, not the normal 'Ssssss' the stock one makes. Perhaps I have a nastly boost leak after all? How is that possible?? I boost leak tested my system AGAIN and it holds 30PSI no problem! The regulator on my compressor was set at 30PSI... this could mean it's reading the pressure as 30 at the gauge, outputting 30PSI, not that the tubing sees that because of a potential leak?! I don't hear any leaks when I test. I'm going to get a guage and install it on the boost jig itself to see what pressures the pipe actually sees.

I don't want to keep throwing $$ at my car. Yea, I spent $600 and 2 weekends doing the turbo swap, yea I have a better turbo now so that's cool, but the old one would have held out a bit longer, especially since I'm only boosting 10% more than stock. I could get charge piping, a new map and tmap sensor, but what else could be wrong? BPV? BPV solenoid?? turbo wastegate solenoid? The actuator itself? Blown out injector seals? Leaking intake mani?!

Totally and utterly stumped. I just want my quick car back :\

 

bump? This is a bit more technical than I can grasp. I will try what I mentioned but I don't want to throw money @ it. Going to pull DP today and run open turbo, if that isn't it I'll order MAP & TMAP sensors from rockauto, hoping for the best... Still can't find this damn leak.

 

Should have known... the 2nd was clogged too!

Open turbo test to verify the cat is to blame: https://www.dropbox.com/s/8le88q06re...52.48.mov?dl=0 Car sounded like a turbo diesel

Another little video for your entertainment, my BPV is much louder now? I added an extra spring from a hand sanitizer dispensor at my hospital so the BPV has twice the spring strength and sound slike this: https://www.dropbox.com/s/sxl4l8mav9...56.58.mov?dl=0 (yes I said BOV in the video, whoops)

Cat looked fine on the exit side, must have melted pretty bad on the inlet side where I can't see. Smashed the 2nd cat out too, now she's running 100% again.

Thanks to all who helped lend their ideas to help me out, much appreciated

 

lies,