jmiller15

Okie, so I finally got my DP installed tonight, took me 2 hours of sweat and all the body strength I had but I got it...

My first initial thought was wow, this sounds great, and it does...

Few issues, the gasket from the turbo flange to the dp, does that absolutely have to be removed? Mine never came out, I think? Or is there even one on the stock DP?
Replaced the second gasket that came with the DP though at the back side of the DP.

Okay so took it for the a drive, after install I got underneath and checked for any exhaust leaks etc... but I couldn't smell any... What would an exhaust leak at the flange - dp joint sound like? Would it be a whistling noise or would I hear anything at all?

Second, I have a major vibration now.... it just sounds as if it is right where my flange/dp joint is, its loud and it vibrates my entire car.... plus its making a weird clunking sound... could it be that I jarred loose the heat shielding?

I doubt it is from not being properly tightened because when I put the bolts back on they were so tight I couldn't move them another MM...

Any ideas?

Frogstofall

iTrader: (1)

The O2 housing to DP flange does have a gasket. Its an O-ring style metal gasket. If you don't replace it, you may or may not get a leak. Its sorta hit or miss. My DP (Bad Mab) came with a normal style exhaust gasket that I added in. Has worked great.

An exhaust leak at that flange would look like a black mark at some point around the flange. Almost like the thing farted and left a black carbon stain. It would sound like someone saying, "SHHHHHHH!!" really loud while you accelerate.

The vibration is most likely from the aluminum heat shield. You may have bent it in a manner that it is now touching the body of the car or the DP itself. Check that.

surfdude979

There is a stock gasket it's a simple O ring that is recessed in the turbo flange, if that's still in there your good you don't the the gasket that came with the DP. I have heard it's better to just run the stock gasket because of how it recesses so that's what I did and mine is working out great

As far as your Vibration, what DP are you running and is it catless? if Catless do you have the defouler or is it angled because your o2 sensor could be vibrating against the heatshield and that's my best guess. jack the car up and bed that heat shield a little bit and see if it goes away

surfdude979

apparently i was slow at typing cause i just said the same thing ^^ lol

jmiller15

Turbo xs catless... the O2 housing is actually a straight pipe to the right on the driver side..
I am going to check the heat shielding now, I probably bent it in my struggles getting my bolts off lol!

jmiller15

The SHHH is only at WOT, otherwise I don't hear it... would I throw a CEL?

AND only under load, doesn't do it in neutral

surfdude979

If its as tight as you say and it's seated right your prob fine I would fix the heat shield and then listen for it if it just sounds like turbo spool that you normally hear with a Sri or cai your good call it a day

jmiller15

Okay vibration, definitely from the heat shielding.... will fix that tomorrow..

I have a quick video of a quick WOT in 2nd, lemme know if this is leak or spool, its hard to tell :/

first vid is WOT run, and 2nd is the vibration/rattle etc...






Don't mind the squealing in the second video, dealership issue... something to do with my brakes, can't figure it out :/
If there was an exhaust leak it would be constant correct, like even in neutral and revving you'd still hear it?

jmiller15

Any more input?

surfdude979

on the first video it just sounds like your riding the clutch and then you drop it so the wheels break loose, shot a better vid something like a 35-60 accel vid and i'll be able to hear it more but try it in 3rd too cause the turbo spool is pretty loud when your in low-mid rpm

in the second vid doesnt' really sound like much, did you check the heat shield?

jmiller15

First vid is WOT haha no clutch involved just likes to break loose, I'll shoot one mor
Tonight but I am pretty sure it's just spool, I've just never heard it like that before.
This is my first turbo car and first really modded car.... If someone could post a video of spool on a catless dp itd be easier for me to get an idea... My afrs are steady so I would expect if I had a leak id either throw a code or be running leaner than norm.

2nd video ... Videos suck sometimes I did check my heatshield a d adjusted it ... Haven't heard the noise again today... But I am at work..

jmiller15

Okay vibration still not fixed, so I jacked it back up went under... re tightened all the bolts... fiddled with the heat shield again.... Still nothing its not as bad as it was, but still noticeable after awhile... Any ideas?

Here are 2 more videos, 3rd gear 60KMH to 100 pull
2nd is the vibration... its only really bad when I am in reverse and slow off the clutch... and when downshifting... everything that normally creates the most vibration on the exhaust... I double checked the tightness of the hangers etc.. everything... nothing jumps out at me...

surfdude979

your good as far as the exhaust i don't hear any leaks i still don't hear anything on the vibration part but maybe my ears suck

jmiller15

yea when I was under I started it up, I couldn't hear anything, or smell anything... and the flange didn't have any sooty spots on it... I tightened everything up just to be sure... Its been a few heat cycles so I got a tiny bit of play on a few bolts...


as for the vibration listen close, it sounds as if you took say... a vibrator lol and put it on a table...

soundjunky

iTrader: (4)

did you simply attempt to tighten, what was already tight?

when you crawled under your car (the second time, I would have suggested loosening all hardware, making sure it's in straight, and that you have ample clearance around the O2 bung... then slowly (as in stagered, in steps) tightened the DP first at the turbo, then at the catback.

I have R&R'd mine twice - and I have had no issues...

Then again I am also running a different DP than you. *shrugs*

jmiller15

Well that might be a good idea if I continue to have problems, but I feel as if the install went well, everything fit up really nice and there were no issues (other than stubborn bolts). I basically just read that after a few heat cycles the bolts should be retightened just to make sure so I tossed a ratchet on there and cranked it a little bit as much as I could.

O2 bung as a ton of clearance as it is welded to the side of the DP.

My install started removing flange down to catback, than reverse I started at the cutback up to flange.

I do admit, when attempting to get the bolts off on the flange/dp side, I did have to push up on the heat shield quite a bit as I was doing my install on ramp jacks, not a lot of clearance :/
But I re-adjusted everything tonight again, to no avail though... Thinking I might actually take it to an exhaust shop... I have very little time sadly after work and this has eaten up 3 days so far in which I really should have been doing other things haha!

However, that being said the only issue I am having is the vibration, and I can't figure it out...
I have been keeping a close eye on my AFR's and have seen normal readings, so that does help me confirm that exhaust leak is not as much of a concern

This is the guide I used.

https://www.cobaltss.net/forums/08-1...46/index2.html

themacguy

You need at least a finger width's gap between the downpipe to cat-back flange and heatshield, or it will vibrate. $60 at an exhaust shop to fix mine up. You need heat. Heat to adjust the hangers.

Cobe

Hahahaha I started to read yours and was like wait i just read the same damn thing! Haha

jmiller15

This, I didn't look close enough and at the right angle, in anycase the dp/catback connection was pretty much pressed right up to the heatshield, just with the way the new dp fit, they tried to heat and bend a rear part of the exhaust and than the hangers...but didn't have any luck so they had to make a cut in one of the bends and re-weld, now it sits perfectly..

wol-shiver

Had the same problem with the same pipe. ended up being a crushed flex pipe that sat in the box for too long and it seemed to retain this oval shape. this was 2 weeks ago.

when engine is deceling in 3rd and 4th it rattles at that exact spot...

box it was shipped in was perfect...they make good products...refused to help me because i bought it from a local vendor and not direct, i had a bill and turboxs box pictures and they still pushed me away...

might be my fault and not dissing their service, but i am putting it out there. i am sure if i was a us customer and shipping was easier they would of helped...

jmiller15

So gf was in my car today first time since the dp install... My old lady hates my car, but while driving today she said and i quote "you muffler sounds awesome"