Hidden Boost Leak

[jwahl16]

Ok so i have spent all day yesterday and today doing boost leak tests. I have gone from being able to hold 0 psi to 4-6 psi. It seems i have a huge leak right around where my hard lower intercooler pipe meets the stock sidemount intercooler. I can hear it hissing out when i turn off the pump. I have sprayed down every coupler, the pipe, and the intercooler a dozen times but to no avail. I just can't seem to find where it is leaking from. Is there anything else in that area that would be leaking that i am forgetting?

Thanks

 

[dsmvenge]

check your exhaust mani bolts and turbo bolts Ive had mine back out

 

[jwahl16]

This is a boost leak, not an exhaust leak. It is more towards the intercooler, not the turbo area. The turbo compressor cover is NOT leaking.

 

[anokh3]

Do you have a J-Pipe out of the turbo to the intercooler? I'd check that if you do. Thought I had a leak at the lower intercooler pipe and was spraying forever trying to find it. Then I accidentally hit the J-pipe right after the turbo with the spray and found it there.

 

[9!'clipseDOHC]

The only other thing in that area is the bcs (if you still have it). Could be a tear/hole in the coupler, or a bent pipe (benst so that its no longer a perfect circle), or even a hole in the pipes or leaking weld on the intercooler. Keep checking, don't give up.

 

[Bud92gsx]

This is a boost leak, not an exhaust leak. It is more towards the intercooler, not the turbo area. The turbo compressor cover is NOT leaking.

Wrong..Having a pre turbo exhaust leak Is a boost leak, because if your exhaust is leaking before the turbo..It's not going to boost like it should..Recheck your turbo to manifold bolts just in case..And your manifold to head bolts..

But other wise follow the suggestion given in the previous posts..

 

[9!'clipseDOHC]

Wrong..Having a pre turbo exhaust leak Is a boost leak, because if your exhaust is leaking before the turbo..It's not going to boost like it should..Recheck your turbo to manifold bolts just in case..And your manifold to head bolts..

But other wise follow the suggestion given in the previous posts..

He's doing a boost leak test (I.e. pressurizing his intake tract with compressed air). He's not building boost with his exhaust while doing a boost leak test.

 

[TJCTalon]

^ no your wrong. That is not an exhaust leak. Its a boost leak. Just because the turbo isnt running like its suppose to doesnt mean its a exhaust leak.

Wrong..Having a pre turbo exhaust leak Is a boost leak, because if your exhaust is leaking before the turbo..It's not going to boost like it should..Recheck your turbo to manifold bolts just in case..And your manifold to head bolts..

OP check the intercooler itself. And like said above spray all vac lines.

 

[Palmetto_TSi]

^ no your wrong. That is an exhaust leak. Not a boost leak. Just because the turbo isnt running like its suppose to doesnt mean its a boost leak.



OP check the intercooler itself. And like said above spray all vac lines.

WOW!!!! pretty ballsy to call a wiseman wrong. If the OP hears hissing caused by an airleak at the SMIC, I think it's safe to say you don't have to be a wiseman to know there is a boost leak down there. OP also states that he can only hold 4-6 PSI ON THE BOOST LEAK TEST. Boost leak test doesn't have anything to do with the exhaust, and he can hear the leak, just can't seem to find it.

 

[Bud92gsx]

He's doing a boost leak test (I.e. pressurizing his intake tract with compressed air). He's not building boost with his exhaust while doing a boost leak test.

You make a good point tho..A boost leak could be the end of it all together..If hes loosing pressure in the IC system then yes boost leak period..

But It would also make sense to make sure the head to manifold bolts are tight, and the manifold to turbo bolts are tight..If that's a factor a pre turbo exhaust leak that will make the turbo not boost like it should too..

 

[TJCTalon]

Did I quote the wiseman? No I quoted the guy above him. He beet me before I could post but thanks.

 

[Palmetto_TSi]

then why are you saying it's an exhaust leak?

 

[9!'clipseDOHC]

But It would also make sense to make sure the head to manifold bolts are tight, and the manifold to turbo bolts are tight..If that's a factor a pre turbo exhaust leak that will make the turbo not boost like it should too..

It would make sense to check it yes, but that has nothing to do with his "hidden boost leak". That would be an exhaust leak like mentioned above.

TJCTalon, I know who you were reffering to. Its all good.

 

[Gump1114]

i would be if you're hearing the leak from down around the intercooler, but dont see a leak at the pipes, it's the intercooler itself. Check it for any damage, nicks, or dents.

 

[Bud92gsx]

I consider exhaust leaks to be after the turbo, unless you have a huge crack in the manifold of turbine housing you know what Im saying..But Since this is a IC system pressure problem, that's definatly a boost leak..Don't boost leaks just make everyone one happy camper....Especially hidden ones..

Like Gump said it could be in the IC itself..You know from over the years with rpcks and crap possiblt hitting it..The way I checked mine..Was I filled it with water, and made sure it didn't leak..But that the super cheap way if you don't have acess to a blt...

 

[9!'clipseDOHC]

I consider exhaust leaks to be after the turbo, unless you have a huge crack in the manifold of turbine housing you know what Im saying..But Since this is a IC system pressure problem, that's definatly a boost leak..Don't boost leaks just make everyone one happy camper....Especially hidden ones..

The exhaust starts as soon as it leaves the cylinders. It doesn't matter if you have a leak between the manifold and the head, the manifold itself, the turbine housing, the o2 sensor housing, the downpipe, flex pipe, etc. If burnt gas is escaping from the car before it is intended... its an exhaust leak.

Exhaust leaks and boost leaks are very different. Boost is the air pressurized by the turbo. Exhuast is whatever is left after the combustion cycle. They are very different and should not be confused. Please top trying to justy your statement that a "pre turbo exhaust leak is a boost leak". That is incorrect. It will keep the turbo from spoolling like it should, but that in no way makes it a boost leak.

 

[anokh3]

If the BLT can't seem to hone in on the leak and you're pretty sure its in the intercooler area... I like 91'clipseDOHC idea of filling it with water. However, might as well use gasoline or a can of brakeleen so you can clean the intercooler out while you're at it

 

[jwahl16]

Ok everyone thanks for your help i found the leak (well my dad did haha). It turned out it was the underside of a coupler that i had to readjust and double clamp. Now i can build 11 psi, its not perfect but its much better than the 0 psi i started with.

And in regards to the boost vs exhaust leak,9!'clipsedohc is right, i am testing for boost leaks and a preturbo exhaust leak would not appear in the test. On the other hand, i do have some of those too, hehe.

Thanks everyone

 

[LiquidX]

You could close off the intercooler piping to allow pressurization to occur in the pipe itself and not travel to the intake manifold and beyond. This will allow you to centralize on where the leak is occurring. If anything, re seat your couplers and clamps and if that still doesn't work, try taking the IC off and running a cleaning solution through it (liquid). This will clean out any oil and if there is a leak it should present itself.

Another option with the IC off is to cap off one end, pressure test the other end and submerge it under water.

Are you on hard pipe or the stock rubber hose?

Never mind now

Make sure when you contine your test you check every component that sees vacuum or positive pressure. Rotate the TB as well as the shaft seals are a common leak point as well as the lower injector seals. It also helps to pinch off the PCV line incase you have a leaking PCV.

 

[Bud92gsx]

He's doing a boost leak test (I.e. pressurizing his intake tract with compressed air). He's not building boost with his exhaust while doing a boost leak test.

The exhaust starts as soon as it leaves the cylinders. It doesn't matter if you have a leak between the manifold and the head, the manifold itself, the turbine housing, the o2 sensor housing, the downpipe, flex pipe, etc. If burnt gas is escaping from the car before it is intended... its an exhaust leak.

Exhaust leaks and boost leaks are very different. Boost is the air pressurized by the turbo. Exhuast is whatever is left after the combustion cycle. They are very different and should not be confused. Please top trying to justy your statement that a "pre turbo exhaust leak is a boost leak". That is incorrect. It will keep the turbo from spoolling like it should, but that in no way makes it a boost leak.

I know the difference...And I know I'm technically incorrect..I just wanted to tell you were I was coming from, being incorrect or not...I Just consider a pre turbo exhaust leak a boost leak cause exhuast spins the turbo..And if your loosing exhaust pressure your not going to be spinning the turbo as fast as it should..That is my reasoning..Like I said I know it is incorrect but I just wanted to let you know where the reason for my madness was coming from..

 

[9!'clipseDOHC]

Ok everyone thanks for your help i found the leak (well my dad did haha). It turned out it was the underside of a coupler that i had to readjust and double clamp. Now i can build 11 psi, its not perfect but its much better than the 0 psi i started with.

And in regards to the boost vs exhaust leak,9!'clipsedohc is right, i am testing for boost leaks and a preturbo exhaust leak would not appear in the test. On the other hand, i do have some of those too, hehe.

Thanks everyone

Glad that you found it! That will be a big improvment going from holding 0 to 11 psi. Boost leak tests can be a pain sometimes but they are very important and the more you do them the easier they will get.

 

[jwahl16]

Glad that you found it! That will be a big improvment going from holding 0 to 11 psi. Boost leak tests can be a pain sometimes but they are very important and the more you do them the easier they will get.

Yeah thanks, i turned down the boost until i find them all. I spent 7 hours today finding and fixing leaks! Hopefully next time (sometime soon) will be easier.

 

[68442]

I had one of those mystery leaks in the same area. Mine was holes.

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