Up-pipe, header leaking?

[jproy12]

So did my UP and DP install, and I was wondering, I got new gasket all around, bolted everything to factory specs, which is around 26ft-lbs.

 

So what I wanted to know is that, would I be able to hear it if I had an exhaust leak at idle from the headers to the engine, the header to the UP or the UP to the turbo?

 

I did a couple WOT runs after my re-flash and all, and rechecked under the car, all the connections and I don't see any black (carbon deposit) anywhere, which I assume its good! Right? Would I be able to see something after a couple runs?

 

Its only when i punch it, around 3000rpm I get a weird noise, somewhat likes its leaking, but at idle and just revving, i cant hear anything... It seems to be only under load, is it normal?

 

JP

[jproy12]

I've looked on youtube, and it seems like I'm not experiencing a up-pipe leak or anything... I would assume I'd be able to hear it at idle.. or a bit under throttle, which I'm not!

 

Someone on my local forum mentioned my intake...I didnt think of the intake.. I have a stock intake with K&N filter... Would that be a louder noise than usual at 3000 rpm, with the addition of an STi catless UP?

 

JP

[jproy12]

So I did more research, and it seems like i would hear a whistle or sound like a tractor if i had a leak anywhere, correct?

 

What would be the disadvantage of having a leak in the piping before the turbo? Would I get less "power"? Would I notice something, even if its a small small leak, would I hear it whistle?

 

Thanks

JP

[TSiWRX]

You'll typically hear much more intake and exhaust tract noises, as well as turbo noise, after the UP/DP: typically, after the UP/DP change-over, most owners with average hearing and even a TBE that's not too loud will actually hear the turbo spooling, which is something that, when using factory pipework, tends to be muted.

 

The fact that you have a K&N in the mix should not make much difference, in terms of the sound levels - as that should remain the same.

 

A pre-turbo or post-turbo leak in the exhaust side of the equation can both sound like a John Deere tractor underhood. "Whistling" sounds are typically associated more with the intake tract side of things (i.e. TMIC fittings on both ends).

 

While a big enough intake-tract leak will certainly cause noticeable driveability problems, even a pretty big UP leak (at either ends of the UP) can still have your car seeing "Stage II's" target boost levels.

 

Mechanically speaking, the diagnosis is simple - visuals, like you're doing, as well as simply getting your hands around the critical connections to feel for any leaks. Of course, the latter needs to be done on a cold/cool car , and typically, you'll have about 3 to 10 minutes of working time, depending on just how long you let the car sit prior to the test, how cold the day is (that 10 minutes? yep, that's, like, in our snowy and icy winters ), and, of course, how much heat you/your hands can tolerate.

 

Spraying the connections with soapy water can also help visualize leaks.

 

One old trick that seems to work well on the BL/BPs is to re-torque the hardware after a couple of heat-cycles.

[jproy12]

You'll typically hear much more intake and exhaust tract noises, as well as turbo noise, after the UP/DP: typically, after the UP/DP change-over, most owners with average hearing and even a TBE that's not too loud will actually hear the turbo spooling, which is something that, when using factory pipework, tends to be muted.

 

The fact that you have a K&N in the mix should not make much difference, in terms of the sound levels - as that should remain the same.

 

A pre-turbo or post-turbo leak in the exhaust side of the equation can both sound like a John Deere tractor underhood. "Whistling" sounds are typically associated more with the intake tract side of things (i.e. TMIC fittings on both ends).

 

While a big enough intake-tract leak will certainly cause noticeable driveability problems, even a pretty big UP leak (at either ends of the UP) can still have your car seeing "Stage II's" target boost levels.

 

Mechanically speaking, the diagnosis is simple - visuals, like you're doing, as well as simply getting your hands around the critical connections to feel for any leaks. Of course, the latter needs to be done on a cold/cool car , and typically, you'll have about 3 to 10 minutes of working time, depending on just how long you let the car sit prior to the test, how cold the day is (that 10 minutes? yep, that's, like, in our snowy and icy winters ), and, of course, how much heat you/your hands can tolerate.

 

Spraying the connections with soapy water can also help visualize leaks.

 

One old trick that seems to work well on the BL/BPs is to re-torque the hardware after a couple of heat-cycles.

 

Wow, thanks for the usefull info!

 

I did a couple WOT runs this morning, and it seems fine, I may just no be used to the fact that it's louder than OEM! Would a catless UP cause more noise in the system, I am running an STi UP, an Invidia catless DP and a full cobb catback, seems louder!!

 

I'll check all connections, but it wont be easy, how to you manage to re-torque the nuts under the DP? I did a couple WOT yesterday (6-10 WOT) and after that checked all connections, and seemed fine! I may end up re-torquing them! When you guys say a couple of heat-cycles, what does it mean exactly?

 

Thanks again, and it seems like its normal... I'll get used to it!

 

JP

[TSiWRX]

Wow, thanks for the usefull info!

 

NP. Glad to help.

 

I did a couple WOT runs this morning, and it seems fine, I may just no be used to the fact that it's louder than OEM! Would a catless UP cause more noise in the system, I am running an STi UP, an Invidia catless DP and a full cobb catback, seems louder!!

 

Yes, it'll all be louder.

 

I'll check all connections, but it wont be easy, how to you manage to re-torque the nuts under the DP?

 

^ Lots of extensions and U-joints. I honestly can't remember, but when I close my eyes, it seemed that I had one universal along with either a 3" or 6"-extension. I do apologize, but it's been a while - I went "Stage II" back in the 3rd quarter of 2005.

 

I did a couple WOT yesterday (6-10 WOT) and after that checked all connections, and seemed fine! I may end up re-torquing them! When you guys say a couple of heat-cycles, what does it mean exactly?

 

I waited for a clear week, before doing mine, so that I could leave the heat-shields off and re-torque. I simply went back to-spec after a couple of days' driving, and then hit it again before putting everything back in-place, but I think what you're doing now should be fine, too.

 

The first time I did mine, I actually forgot to re-torque the passenger-manifold-to-UP connection, and one of the bolts there completely backed out after a winter's use, and the other was barely on. That's pretty much how I know that you can still make target boost, even when things are not Kosher any more (my lack of experience at that time said that only post-turbo leaks could make it sound like a tractor, yep, I was wrong ). Going back, using the above procedure (which is what I did with all the other hardware, I have no idea how I managed to miss what I did , but apparently, I did!), I haven't had any problems, since - and to those who would say otherwise, that's with the infamous Crucial Cu-gasket, too.

 

[anotherbrian]

As far as diagnosing from sounds, yesterday I developed (what I'm hoping is) a UP leak. I've had a Crucial UP and shortie-DP installed for the last year. I believe factory gaskets were used.

 

Sound started while accelerating from a stop (not-WOT, but close to it) as a very loud squeal that sounded like a belt was slipping. Subsequently, under boost, it sounded like a loud valve-like clicking sound (speed of clicking correlated to RPMs). In neutral, the engine sounded normal if revved (*whew*, not valves/pistons).

 

Car is at the shop now, and hopefully it'll be an easy/quick/cheap fix.

[moncur_6]

I did an invidia up/dp install not too long ago and had an exhaust leak after getting everything back together (between UP and turbo). With the stock cbe, my car sounded MUCH more like a boxer, almost STI-ish. Plus the turbo was much much much louder and I felt like the car had lost at least half of it's power.

[LowFast]

As far as diagnosing from sounds, yesterday I developed (what I'm hoping is) a UP leak. I've had a Crucial UP and shortie-DP installed for the last year. I believe factory gaskets were used.

 

Sound started while accelerating from a stop (not-WOT, but close to it) as a very loud squeal that sounded like a belt was slipping. Subsequently, under boost, it sounded like a loud valve-like clicking sound (speed of clicking correlated to RPMs). In neutral, the engine sounded normal if revved (*whew*, not valves/pistons).

 

Car is at the shop now, and hopefully it'll be an easy/quick/cheap fix.

 

Update? What did they find, I have developed the same loud tick when in boost, not throwing any codes or having other issues. Just the loud tick when going into boost at about 3000-3500RPM.

[jproy12]

So small update! Been driving the car for the past 3 days and everything seems fine!

 

If I had a really small leak somewhere, how could I hear it? At idle? Under load? WOT?

 

Thanks

JP

 

Ohh.. Loving stage2 wow does it ever pull!

[TSiWRX]

So small update! Been driving the car for the past 3 days and everything seems fine!

 

 

If I had a really small leak somewhere, how could I hear it? At idle? Under load? WOT?

 

In all honesty, you probably won't hear a thing, if it's a really small leak - particularly if you also have an aftermarket cat-back or noisier tires.

 

Quieter tires, factory exhaust, with the windows down -or up- and no fan blowing, you're most likely to hear something in the small window of quiet before your road-speed gets up to where the wind-noise obscures things (and that's why the "or up" part may also work to your favor, as it will counteract road-noise, but again, it's totally dependent on the exact scenario).

 

Small leaks are really hard to "hear," but should be visible with the spray-bottle method or be able to be felt with your hand.

[jproy12]

Thanks for the reply!

 

I did the soapy water thing 2 days ago and didn't find anything! So all in all, most likely normal!

 

I assume the catless UP also has a factor in the sound? Correct? The dp you can hear the turbo wine! I love it!

 

JP