Boost leak problem seems unsolveable?

[octanepwr]

Hi all

I am new to this forum. It seems like a great resource as the Airtrek Turbo is quite rare at least in NZ.

I have had my standard Airtrek Turbo for a while and it had a boost leak when I bought it. I figured it was an easy fix and got it cheap.

First I put some better clamps on the flexible piping on each side of the intercooler and the outlet cold side from the turbo. This did not solve the problem. At one point it felt like it did and then the car misfired instead, so I replaced the plugs with new platinum Bosch type and it went back to this boost leak syndrome. The old plugs were in bad shape anyway.

I have replaced the factory BOV with a Turbosmart plumb back. This did not solve the problem.

Only leak I found while testing with a pressure tester where I pressurised from the turbo side of the intercooler was one of the throttle body slide seals so I replaced the seal on the spring side.
I did not change the throttle slide seal on the throttle position sensor side of the throttle body as it seemed good and tight with no rips. The throttle cable spring side seal was ripped.
I highly doubt that the throttle body slide seal leak could make this much of a hiss anyway!

I pressure tested again after replacement of the one slide seal and found no leaks, yet still have this hiss while driving.
I have no boost gauge unfortunately as car is completely stock aside from the replacement plumb back BOV. I pressure tested to 12psi or so and factory boost I believe is less than this so should have found the problem. I also shook all piping and move the throttle cable while it was at pressure and had no leaks.

See video below!
http://youtu.be/z5CA-GgbAwU

Any ideas to solve this?

Thanks

 

[vr2turbo]

Looks like you better fit a boost meter to check it out. It will be more correct....

 

[octanepwr]

Turns out I was looking in the wrong place.

Is it possible to weld up the cast manifold?

Big crack by cylinder 1.

Is this a common problem?

 

[vr2turbo]

Turns out I was looking in the wrong place.

Is it possible to weld up the cast manifold?

Big crack by cylinder 1.

Is this a common problem?

Not sure if that can be welded. Whether common problem need air trek owner to comment.
Similar Mitsu engine, my VR4 seems to be common problem. I am on my second set. After my turbine failed, remove and found manifold cracked, so I got a 2nd hand unit fitted until now...

 

[^pomen_GTR^]

Turns out I was looking in the wrong place.

Is it possible to weld up the cast manifold?

Big crack by cylinder 1.

Is this a common problem?

with that amount of crack...i would say u will be better getting the aftermarket turbo manifold instead of welding that up....afraid it would getting bigger until the manifold worth as scraps...

 

[trustgtr]

cast iron can b welded but probably the cracks formed from inside hence probably give u a releif for a short while. best is to replace it, keep in mind the more you run the car with the leaks your turbo is taking lot of stress.

 

[stutzedward]

This is a common problem. The reason is because during rainy days, our top airscoop opening drips water onto the hot manifold, hence crack is very common.

It can be welded but I heard some say that it will not last. When mine cracked, I upgraded the turbo and got the whole set from Evo 7.

Make sure you have the heatshield on all the time. Getting performance manifold (banana type) will prone to cracks too due to the leak from the airscoop on the hood. So advise to use standard manifold with heatsheild. Good Luck!

---------- Post added at 03:50 PM ---------- 6 hour anti-bump limit - Previous post was at 03:46 PM ----------

This was my crack last time.

 

[vr2turbo]

Mine crack near the turbine area, seems also common problem....

 

[octanepwr]

cast iron can b welded but probably the cracks formed from inside hence probably give u a releif for a short while. best is to replace it, keep in mind the more you run the car with the leaks your turbo is taking lot of stress.

Why does it stress the turbo more?

---------- Post added at 06:30 PM ---------- 6 hour anti-bump limit - Previous post was at 06:25 PM ----------

This is a common problem. The reason is because during rainy days, our top airscoop opening drips water onto the hot manifold, hence crack is very common.

It can be welded but I heard some say that it will not last. When mine cracked, I upgraded the turbo and got the whole set from Evo 7.

Make sure you have the heatshield on all the time. Getting performance manifold (banana type) will prone to cracks too due to the leak from the airscoop on the hood. So advise to use standard manifold with heatsheild. Good Luck!


The heatsheild was always on so I doubt it is water through the scoop as the cracked bit is covered by the shield and the only bit exposed is the manifold flanges to the cylinders. Possible though if the drip runs down though.
Replacing with another standard manifold sounds like it will just fail again.
I like td04 for the low torque and not keen on changing turbo and associated costs. I expect there is not many aftermarket non custom manifolds for this turbo?
did yours leak and sound like my video?

 

[stutzedward]

I agree with you that it'll crack again in long run. Just part of wear and tear.

 

[octanepwr]

Doe an evo manifold work as a replacement and if so does it have the same cracking problem? I assume I would need new intake pipe and exhaust off the turbo even sticking with td04.

Did yours sound like mine when cracked?

 

[ixeo]

All will eventually crack..regardless if its evo, aftermarket or original airtrek.

 

[stutzedward]

Doe an evo manifold work as a replacement and if so does it have the same cracking problem? I assume I would need new intake pipe and exhaust off the turbo even sticking with td04.

Did yours sound like mine when cracked?

It will crack eventually, just matter of time. ANd you cannot use Evo manifold on TD04. It's different.At least that's what I am aware off. Here a pic with TD05 and it's manifold.

 

[phillipbmx]

Hi, sorry to bump up an old thread but I have the same issue. Hissing and loss of power at high revs. Was the cracked exhaust manifold the cause of this? Just seems that its a very weird noise for a manifold leak and also mine doesn't do it every time i floor it and I feel a cracked manifold would act in the same manner every time. Its much more common to happen to me when im in lower gears but sometimes 3rd or 4th.
I am still going to check my manifold as this seems to be a common problem.

Cheers

 

[stutzedward]

Hi, sorry to bump up an old thread but I have the same issue. Hissing and loss of power at high revs. Was the cracked exhaust manifold the cause of this? Just seems that its a very weird noise for a manifold leak and also mine doesn't do it every time i floor it and I feel a cracked manifold would act in the same manner every time. Its much more common to happen to me when im in lower gears but sometimes 3rd or 4th.
I am still going to check my manifold as this seems to be a common problem.

Cheers

If the crack is small on the manifold, you'll hear the hissing sound much louder when the engine is cold. When it's warm, it becomes softer as the metal expands and covers the crack better. Yes, it becomes more apparent when your boost is higher. Open up the manifold cover and check. If there's slight hairlines with dark powder like around it, it's most likely the crack. Hopes this help.

 

[vr2turbo]

Most probably a crack, if not check for broken bolt. I had one bolt that snap causing a leak also. Mitsu many issues with crack exhaust manifold.....

 

[phillipbmx]

Thanks for the quick replies and I am more convinced it could be the manifold now but just to confirm for you guys my car seems to run fine 98% of the time. Lets say i plant my foot from stand still, it will get up around 5000rpm and then a sudden "SSSSHHHHHH" noise and a instant drop in power. If i do it from rolling start, say in 3rd, the chances of it doing anything wrong are very minimal but in some cases i will get the hiss and loss of power. Never really does it in 4th and 5th even though bost is higher in these gears.
I always thought exhaust leaks make the car sound more like a tractor and the effects would be more frequent and constant.
Will be inspecting the manifold when I get a chance.

 

[stutzedward]

Leak before turbo, you get hissing sound cos the air is compressed to rotate the exhaust turbine.

Leak AFTER turbo, you get that typical tractor noise...

 

[vr2turbo]

Thanks for the quick replies and I am more convinced it could be the manifold now but just to confirm for you guys my car seems to run fine 98% of the time. Lets say i plant my foot from stand still, it will get up around 5000rpm and then a sudden "SSSSHHHHHH" noise and a instant drop in power. If i do it from rolling start, say in 3rd, the chances of it doing anything wrong are very minimal but in some cases i will get the hiss and loss of power. Never really does it in 4th and 5th even though bost is higher in these gears.
I always thought exhaust leaks make the car sound more like a tractor and the effects would be more frequent and constant.
Will be inspecting the manifold when I get a chance.

In that case check your waste gate too because like you mentioned higher rpm only it comes. Probably check the Vacuum hoses too

 

[phillipbmx]

I feel like an evo manifold, TD05 and FMIC should fix my problem then
Unless its a vacuum hose...

 

[stutzedward]

Hahaha.... there you go.... good excuse here for the 'fix'... :top:

 

[vr2turbo]

Hahaha.... there you go.... good excuse here for the 'fix'... :top:

All he needs is a reason......hahhahahhahaha

 

[sarutobi84]

Just to share my exhaust manifold crack due to 'vibration' from the downpipe(exhaust fabricator use short type stainless flexi hose-so when wot and engine move to back and forth the whole exhaust system got pull/stress)
When wot can hear the whole front engine resonannce/vibrate like 'zzzzzz'inggg. Fix the crack by welding and change the flexi hose too long type.no more weird resonance during wot.

Sound like tractor at idle,actually its the exhaust pulse come out from the crack area.(maybe due to my hicam also as the sound goes in pulses)
The drop in power at 5k rpm might be the pressure inside the turbo manifold was abruptly reduce from the leak area to sustain the turbo rpm/boost

 

[phillipbmx]

For the TD05 conversion, will any manifold from evo 4 - 9 mixed with any turbo from evo 4 - 9 bolt up? And as long as i run a evo 7 down pipe it should all match up? And then I just need to sort the fan issue and im good to go? Keep hesitating to buy parts when im not 100% sure.

 

[sarutobi84]

manifold basically the same evo4~9 and will bolt to evo 4~9 turbo.(oil and water line different for evo9 turbo btw as i'm using evo9 base turbo)
Evo7 downpipe will bolt on to evo 789 turbo/turbo outlet only as evo 456 have different turbo outlet housing downpipe flange.it can fit to the earlier(456) turbo outlet with some minor modification btw.

For the TD05 conversion, will any manifold from evo 4 - 9 mixed with any turbo from evo 4 - 9 bolt up? And as long as i run a evo 7 down pipe it should all match up? And then I just need to sort the fan issue and im good to go? Keep hesitating to buy parts when im not 100% sure.