# Exhaust manifold to turbo leak



## fastgascar (Jul 30, 2001)

If you have had an exhaust manifold to turbo leak or even a cracked exhaust manifold, what are the telltale signs? I don't hear any ticking cold or hot, but I do hear a loud swooshing noise while cruising between vac and boost it is louder when the car is cold. Car is now all back to stock until I can figure out where the noise is coming from. It spikes to 10lbs, settles @ 8lbs, when I accelerate the swooshing noise goes away and all you hear is turbo. I have run VAG diagnostics on it and there is nothing out of the normal. CEL is not on. I have been working on this on and off for over a year now. Any suggestions?


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## Dub-Nub (Sep 27, 2005)

fastgascar said:


> If you have had an exhaust manifold to turbo leak or even a cracked exhaust manifold, what are the telltale signs? I don't hear any ticking cold or hot, but I do hear a loud swooshing noise while cruising between vac and boost it is louder when the car is cold. Car is now all back to stock until I can figure out where the noise is coming from. It spikes to 10lbs, settles @ 8lbs, when I accelerate the swooshing noise goes away and all you hear is turbo. I have run VAG diagnostics on it and there is nothing out of the normal. CEL is not on. I have been working on this on and off for over a year now. Any suggestions?


I would suggest doing the following

1) boost leak test

2) seafoam

Normally when you get exhaust leaks you can hear a ticking sound. It doesnt always sound like metal on metal


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## fastgascar (Jul 30, 2001)

*Boost test/Seafoam*

I have pressure tested between the intake and the TB and that is holding pressure fine, once I reattach the TB I hear a hissing inside the engine I am guessing air passing through the open valves. Compression check shows nice consistent #'s across all cylinders. I seafoamed the engine last yr, maybe the condition is worse, so I can try that again early in the AM Saturday, I think I'll lift it up and video tape under the exhaust manifold/DP area as I spray it in.


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## bootymac (Apr 19, 2005)

Your boost levels suggest that there are no leaks... Are you sure this "swooshing" noise isn't your diverter valve?


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## fastgascar (Jul 30, 2001)

*Swooshing possible DV*



bootymac said:


> Your boost levels suggest that there are no leaks... Are you sure this "swooshing" noise isn't your diverter valve?


I kept thinking that too, I disassembled the DV removed the piston and spring(stratosphere) and test drove it, swooshing noise was still there as it tried to build boost, it was very slow as anticipated. Then I tried a stock factory DV from an audi tt 225, results were the same with the (stratosphere)


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## Strah (Oct 26, 2011)

Have u figured out what was ur problem? I am having a very similar problem.


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## groggory (Apr 21, 2003)

fastgascar said:


> I have pressure tested between the intake and the TB and that is holding pressure fine, once I reattach the TB I hear a hissing inside the engine I am guessing air passing through the open valves. Compression check shows nice consistent #'s across all cylinders. I seafoamed the engine last yr, maybe the condition is worse, so I can try that again early in the AM Saturday, I think I'll lift it up and video tape under the exhaust manifold/DP area as I spray it in.


To do a proper pressure test.

Pressurize at the TIP.

Use hose pliers and smash closed the PCV hose just before the PRV

Test at 5 PSI. Fix any leaks.

Re-test at 10 PSI. Fix any leaks.

Do not test above 10 PSI.


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## fastgascar (Jul 30, 2001)

*Replaced the manifold*



Strah said:


> Have u figured out what was ur problem? I am having a very similar problem.


I replaced the exhaust manifold over the weekend, the sound is still there. Power seems up a little. Not sure what else it could be now.


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## fastgascar (Jul 30, 2001)

groggory said:


> To do a proper pressure test.
> 
> Pressurize at the TIP.
> 
> ...


Thanks for the suggestion, unfortunately I don't think its a boost leak it spikes 20lbs and holds
16-17lbs to 5500 then the last 500 RPM's it feels like it studdering, but that maybe a fueling issue now. No CEL and no VAG codes.


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## fastgascar (Jul 30, 2001)

Strah said:


> Have u figured out what was ur problem? I am having a very similar problem.


Find anything new?


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## 05GTIMarine (Nov 11, 2008)

when you first start your car reach back and carefully feel aournd the manifold to turbo area. if there is a small amount of exhaust coming from there then youll have a larger leak on boost. also check your turbo> dp area. the studs come loose and cause a leak. the nuts are 16mm and can be tightened from the top of the engine bay.

i personally have to tighten mine on a bi weekly basis ( damn frankenturbo supplied bolts) you will also notice your mpg go down as a result of the leak as well. 

if you tighten them and the leak is still there go to vw and order new gaskets. they are approx 15 dollars for both and made out of metal. DO NOT buy crappy gaskets from advance or other stores. always use genuine vw hardware


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## fastgascar (Jul 30, 2001)

05GTIMarine said:


> when you first start your car reach back and carefully feel aournd the manifold to turbo area. if there is a small amount of exhaust coming from there then youll have a larger leak on boost. also check your turbo> dp area. the studs come loose and cause a leak. the nuts are 16mm and can be tightened from the top of the engine bay.
> 
> i personally have to tighten mine on a bi weekly basis ( damn frankenturbo supplied bolts) you will also notice your mpg go down as a result of the leak as well.
> 
> if you tighten them and the leak is still there go to vw and order new gaskets. they are approx 15 dollars for both and made out of metal. DO NOT buy crappy gaskets from advance or other stores. always use genuine vw hardware


I have reached behind there when its cold and feel nothing, I have done the Seafoam and see no smoke coming from that area, but a bunch of smoke coming from the exhaust. I replaced the the exhaust manifold gasket and turbo to manifold gasket with the OEM ones when I replaced the manifold 2 weeks ago, the results were the same.


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## groggory (Apr 21, 2003)

fastgascar said:


> Thanks for the suggestion, unfortunately I don't think its a boost leak it spikes 20lbs and holds
> 16-17lbs to 5500 then the last 500 RPM's it feels like it studdering, but that maybe a fueling issue now. No CEL and no VAG codes.


Out of curiosity...have you ever actually tested for boost leaks?

FYI...using your boost gauge as a method of saying you don't have any boost leaks is an automatic fail.


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## fastgascar (Jul 30, 2001)

groggory said:


> Out of curiosity...have you ever actually tested for boost leaks?
> 
> FYI...using your boost gauge as a method of saying you don't have any boost leaks is an automatic fail.


I have done this test http://forums.vwvortex.com/showthread.php?2692757 what I do hear is air inside the intake manifold. Not sure if that is air passing through the overlap of the intake and exhaust valve, but there is no air "externally" escaping.


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## groggory (Apr 21, 2003)

fastgascar said:


> I have done this test http://forums.vwvortex.com/showthread.php?2692757 what I do hear is air inside the intake manifold. Not sure if that is air passing through the overlap of the intake and exhaust valve, but there is no air "externally" escaping.


Did you block off your PCV hose just before the PRV?


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## fastgascar (Jul 30, 2001)

groggory said:


> Did you block off your PCV hose just before the PRV?


I did the test a couple of times, first I did not block the PCV hose and it did blow out white smoke from the oil being forced in. Then I ran the test and blocked off the pipe that connects to the TB and pressurized the system and it was holding pressure, you can watch the intake start to balloon up if you apply to much pressure and once you release the quick disconnect it has alot of pressure being pushed.


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## fastgascar (Jul 30, 2001)

groggory said:


> Out of curiosity...have you ever actually tested for boost leaks?
> 
> FYI...using your boost gauge as a method of saying you don't have any boost leaks is an automatic fail.


FYI: I am not by any means trying to be combative, I appreciate your comments and suggestions. So keep them coming. I am thinking maybe the PRV or a 1 way check valve is bad. Then I wonder what if I do the "engine vaccum line clean up" gettng rid of the SAI and EVAP if that will help, problem is it will throw a CEL. I just can't seem to figure it out. I thought turbo it had the KO3 Sport in it, dumped that and put a KO4 and it has the same noise.


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## groggory (Apr 21, 2003)

Another thought...

Compression test and leakdown test on all cylinders. Maybe something's squeakin by in there?

Also, you may want to check all the 1 way check valves. I am tackling a similar problem on my car. :-( I hate chasing phantom issues too.

I agree, weird issue


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## fastgascar (Jul 30, 2001)

groggory said:


> Another thought...
> 
> Compression test and leakdown test on all cylinders. Maybe something's squeakin by in there?
> 
> ...


I'll run another compression check this weekend. It passed my compression and leakdown test 2yrs ago. All cylinders were very close in range. 

I am thinking maybe the 1st 1 way check valve after the EGR vent tube under the manifold maybe suspect, and I have to do some more research on the proper way to test the PRV. I bought a brand new one and was able to blow through either end with no effort so I am not sure how this part regulates pressure.


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## groggory (Apr 21, 2003)

fastgascar said:


> I'll run another compression check this weekend. It passed my compression and leakdown test 2yrs ago. All cylinders were very close in range.
> 
> I am thinking maybe the 1st 1 way check valve after the EGR vent tube under the manifold maybe suspect, and I have to do some more research on the proper way to test the PRV. I bought a brand new one and was able to blow through either end with no effort so I am not sure how this part regulates pressure.


I think if the intake is in vac, the prv closes.


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