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Everything works fine at 50% or so throttle. If you plug the tailpipe up, you hear no air leaks. I checked all the intercooler connections, and the BOV. Everything is fine. When you get on it, (100% throttle), at say 10psi or so you hear this sound, kinda almost like a game show buzzer, hehe. But, it's perfectly fine at normal-medium driving. Ideas? I'm almost sure this is a leak but I want to see if others have experienced similar...
 

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I also get a wierd sound when going WOT, but it only seems to happen if i go WOT when i first run the car?? or it hasent been started for a little bit?? Im getting it checked soon, so i should know if i have a leak!



Rob
 

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hokieitr said:
Everything works fine at 50% or so throttle. If you plug the tailpipe up, you hear no air leaks. I checked all the intercooler connections, and the BOV. Everything is fine. When you get on it, (100% throttle), at say 10psi or so you hear this sound, kinda almost like a game show buzzer, hehe. But, it's perfectly fine at normal-medium driving. Ideas? I'm almost sure this is a leak but I want to see if others have experienced similar...
My uppipe leaked like that the first time I installed it. Did you replace your top and bottom gaskets with the uppipe? Mine was due to me re-using the stock gaskets. It sealed properly after the new ones. I also used insense to track down where mine was leaking from, chances are yours is leaking from the bottom joint of the uppipe to manifold(seems to be the common spot)
 

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You cant mistake a exhaust leak before your turbo...
your boost guage will tell you ;)

Indian head gasket sealer...
thats what I used on ALL the gaskets pre-turbo

the stuff looks and smells like tar
 

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Same Problem

I just got my uppipe installed this weekend. I'll write a post-op review in a new post, but I have this exact problem as well.

When the car is started after not running for awhile. It sounds fine while off boost, but as soon as boost rises, it emits a high pitched whistle/rattle/???. Hard to describe the sound, it doesn't sound like a typical exhaust leak. It is definitely boost dependant, in that it gets louder as boost builds and is non-existent when off boost.

Here is the thing, it only makes this sound for say 2 minutes of driving, and then disappears. Boost is holding fine, the thing has more power than before, I used new gaskets...what is this sound???

My best guess so far is that it is the turbo heat-sheild vibrating againt the turbo until the sheild and turbo heat up to a point that they don't rub together any more. Does this sound plausible?
 

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Re: Same Problem

jmussetter said:
I just got my uppipe installed this weekend. I'll write a post-op review in a new post, but I have this exact problem as well.

When the car is started after not running for awhile. It sounds fine while off boost, but as soon as boost rises, it emits a high pitched whistle/rattle/???. Hard to describe the sound, it doesn't sound like a typical exhaust leak. It is definitely boost dependant, in that it gets louder as boost builds and is non-existent when off boost.

Here is the thing, it only makes this sound for say 2 minutes of driving, and then disappears. Boost is holding fine, the thing has more power than before, I used new gaskets...what is this sound???

My best guess so far is that it is the turbo heat-sheild vibrating againt the turbo until the sheild and turbo heat up to a point that they don't rub together any more. Does this sound plausible?
You have a leak at the uppipe-manifold junction. The noise is fading as the joint warms and expands, thus causing it to seal. Trust me on this one - I'm pretty much an 'uppipe leak expert' at this point in time. You will not necessarily notice a drop in boost readings, since even a very small amount of vented exhaust there will produce considerable noise.

I have found that the cast oem manifold is largely to blame for the leaks I experienced, and this also seems consistent with what I have seen on others vehicles who have experienced the same problem. Perform a re-installation, and pay particular attention to how the two flange surfaces are mating up to each other when fully torqued. If the faces have not mated squarely, look at the bolts and note whether they are torquing perfectly perpendicular to the sealing surface. Because of the rough manifold casting surface and the stress placed upon that joint, the bolts will usually torque down at a slight angle. You will see what I mean if you get under there and take a look.

-Pace
 

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so what do you think pace? just use gobs of liquigasket on the install? scratch that, the manifold prolly gets too hot for it.

what about sanding the rough surfice of the manifold? i'd love to hear the solution to this before i get one in betty.

dR
 

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I'll take a look under the car when I get a chance, I'll also see if I can re-tourque those 2 bolts without de-installing everything.

Question: IF it IS a slight leak that is sealing up after 2 minutes of driving. Is this a big problem, or something that I can leave be. Doing a complete re-install at this point is not an option I want to consider. I don't think I ever want to do that again!
 

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dark_rex said:
so what do you think pace? just use gobs of liquigasket on the install? scratch that, the manifold prolly gets too hot for it.

what about sanding the rough surfice of the manifold? i'd love to hear the solution to this before i get one in betty.

dR
Well.... very good question! I have not yet found any gasket sealer that is rated hot enough. VHT gasket sealer is not even close.

What I did was make a 'tapered' washer. You can probably buy them this way, but I held a split (locking) washer in some vice grips and then took the dremel and graduated a 180 degree portion of the washer. I only had one bolt that was torquing way off-center, so I used this washer between the nut and the manifold and positioned it such that it would cause the bolt to torque straight. I also added a second (used) gasket along with the new one. I tried (many times) adding second gaskets without the washer trick, but it would only seal for a few days.

This solution sounds whacky, but it worked well for me and my uppipe has been sealing now for 2 months.

You could probably have the bolt-face of the manifold machined to alleviate the situation, but the bolts are also a slightly loose fit in the manifold and that doesn't help either. Another solution might be to re-drill the holes to accept larger bolts, but then you run the danger of drilling them off-center without the proper equipment.

I believe the only completely adequate situation is to use a one-piece manifold-uppipe assembly.

-Pace
 

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jmussetter said:
I'll take a look under the car when I get a chance, I'll also see if I can re-tourque those 2 bolts without de-installing everything.

Question: IF it IS a slight leak that is sealing up after 2 minutes of driving. Is this a big problem, or something that I can leave be. Doing a complete re-install at this point is not an option I want to consider. I don't think I ever want to do that again!
I'd have to say that even when the sound has gone due to the joint expansion, it's likely that you do not have a 100% perfect seal. Personally, that god awful noise bugged the crap outta me even for just a few minutes when cold.

I lost count of uppipe (re)installs around seven or eight. It gets much easier and quicker when you've had plenty of practice. :)

I would like to point out that this is not a problem with any individual vendor's uppipe IMHO. I have read of installation problems with just about every one on the market today, and have personal experience with three different uppipes.

-Pace
 

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pace, what order do you tighten the bolts on the uppipe/manifold assembly? Vishnu reccomends doing the uppipe/manifold connection first, then bolting the turbo/uppipe, then the manifold, then the turbo/uppipe final last 2 bolts.
 

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Discussion Starter · #15 ·
Yep, up-pipe -> manifold, bottom joint :) I jacked it up tonight and found that bastard. So, I'll be buying a new gasket tomorrow. Tish tish on me for thinking I was invincible!

The sound, was the sound of massive amount of finely concentrated exhaust hitting the lower manifold heatshield. Fun!
 

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hokieitr said:
Yep, up-pipe -> manifold, bottom joint :) I jacked it up tonight and found that bastard. So, I'll be buying a new gasket tomorrow. Tish tish on me for thinking I was invincible!

The sound, was the sound of massive amount of finely concentrated exhaust hitting the lower manifold heatshield. Fun!
do you think its ok to leave the heat shield off? i already took the turbo heat shield off and i havnt seen any problems so far...:rolleyes:
 

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Penguinking said:
pace, what order do you tighten the bolts on the uppipe/manifold assembly? Vishnu reccomends doing the uppipe/manifold connection first, then bolting the turbo/uppipe, then the manifold, then the turbo/uppipe final last 2 bolts.
I have used that order, plus variations ;) This has not just been a problem area for amateurs - I have personally witnessed uppipe leaks resulting from professional installations.

Some vehicles do seem to be more prone than others, which could just be variances in manufacturing tolerances. Casting is a somewhat primitive method of forming metallic components and tends to produce articles of low quality (grain size, shrinkage, planar defects, inclusions, porosity, etc.) Some of the problems specifically relating to tolerances and surface defects can be alleviated with subsequent machining; a process most certainly not applied to the WRX manifold.

-Pace
 

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Now that you say it is exhast gas hitting the heat sheild, this makes perfect sense.

I was trying to describe the sound but it sounded like a whistle/screach sound. The whistle is probably the leak, and the screach/rattle sound is probably the heat sheild.

Well, I plan on taking the sheild back off and trying to re-torque those bottom 2 bolts, I was wondering if the heat sheild is necessary to go back on, or can I leave it off for easy access later.
 

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pace- so have you been able to fix any of these leaks by re-torquing the bottom two bolts, or is this a futile attempt, and really needs to be re-installed.

The sound is annoying, but not as annoying as the idea of re-doing the entire job. Do you see any potential problems as far as back-spinning the turbo or anthing like this if I continue to drive the car until I can fix it?
 
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