Boost Problem! Please Help...

[1990TalonTsiAWD]

So i have been having a problem the last 2 months that has made me really mad.
I have yet to find anyone with the same problem.
What happens is when i start my car and let it warm up it runs great at an idle of around 1000 RPMs.
Then i take it out and for the first 5-10 minutes it will boost great and run like a champ.
But after about 10 minutes of steady driving it will only let my get to 5 pounds boost. And when i try to go over 5 pounds it looses all power.
Like it seems like the boost will just totally cut out.
Then after about 25 minutes i have absolutely ZERO boost.
So i have to just crawl up to speed or else the car will not go.

The weird thing is when i let it cool down for 10 minutes then drive it again it seems to get better.

I'm guessing it could be a seal somewhere or gasket that is getting too hot and causing a leak, but where would it be that it leaks all boost that quick? (INSTANTLY)

I have done a cold engine and hot engine boost leak test and fixed a few bad hoses but it still does this.

the only thing i notice when we hot test it is there is a high pitch whistle coming from the front of the engine but i can not pinpoint it.

also i replaced the spark plugs and it did nothing. (alot of people said that would be the problem)

the car is a mod free 1990 talon tsi

any help would be highly appreciated!

 

[dallasadkins90]

sounds like a blown turbo my friend oil is thicker when its cold once it warms up it is easier to push itself past the seals my t25 did the same thing when i bought my latest gsx.

 

[crusada]

I would 1st try to figure out where this whistle is coming from that would be concerning to me. Does your turbo have any shaft play at all?

 

[1990TalonTsiAWD]

how would i be able to check to make sure it is the turbo for sure?
any sure fire signs?

 

[zachyd23]

how would i be able to check to make sure it is the turbo for sure?
any sure fire signs?

Yes, check for shaft play on the turbo ( up an down/ in an out movement of shaft )

 

[dallasadkins90]

how would i be able to check to make sure it is the turbo for sure?
any sure fire signs?

check for shaft play and if your car doesnt whistle when doing the boost leak test its most likely the turbo.
also does it burn any oil while at full boost (or the boost level you get it too)

 

[SkyGrowsCold]

The high pitched whistle your hearing could be a leak near the compressor housing on your turbo possibly your J pipe.

 

[1990TalonTsiAWD]

it has been burning quite a bit of oil lately...and im tearing stuff out to check for shaft play...

 

[dallasadkins90]

it has been burning quite a bit of oil lately...and im tearing stuff out to check for shaft play...

if its burning through the exhaust, also check for oil in the intake pipe and if its in either of these places than its a blown turbo

 

[1990TalonTsiAWD]

well i got to to it and there is no shaft play whatsoever and the inside looks very clean...there was a little oil on the outside of the pipe but i used to have and oil leak above it awhile ago so i think its just residual oil from that. so does that mean the turbo is still good? just so i can for sure cross that off the list...
also on thing i noticed was that the intake hose wasn't really tight..going onto the turbo...could this be a factor? and if so why would it only leak boost after driving for awhile?

 

[slayer450]

I'm still new to these cars so I'm not sure if this would make sense but, you said you had an oil leak and there was oil in your intake. Is it possible that you have a bunch of oil in your intercooler clogging it up and your just heat soaking??

 

[dallasadkins90]

and its not burning through the exhaust ? have you done a compression and leakdown test on the car?

 

[1990TalonTsiAWD]

i have not not done either..im still new to cars and have not gotten far with it yet...i will probably have too cause i am still clueless whats causing this

 

[dallasadkins90]

i have not not done either..im still new to cars and have not gotten far with it yet...i will probably have too cause i am still clueless whats causing this

do that and report back to us turbo is still in the lead for me you dont half to have shaft play for a turbo to be bad does it spin freely when you turn it with your fingers

 

[1990TalonTsiAWD]

yeah i can spin it with my fingers and its not rubbing on anything...and its not spining hard at all but it has a little bit of restriction...sort of like a rubber band is hooked up to it...

 

[dallasadkins90]

yeah i can spin it with my fingers and its not rubbing on anything...and its not spining hard at all but it has a little bit of restriction...sort of like a rubber band is hooked up to it...

hmm.. you dont have an extra one laying around? or a buddy with a 14b u can test with just to check.. also get to the bottom of where the whistling is coming from and do the comp and leakdown test's.

 

[1990TalonTsiAWD]

hmm.. you dont have an extra one laying around? or a buddy with a 14b u can test with just to check.. also get to the bottom of where the whistling is coming from and do the comp and leakdown test's.

well i tighted down everything i could and took it out driving and i couldn't notice any boost problem anymore...i haven't had a chance to drive it for like 30 minutes so im not totally sure if its fixed but i could see the turbo was getting to full boost way faster..i think the problem could have been the intake hose that connects to the turbo because the clamp the was on there didn't tighten down hard enough so i put a better clamp on there..

thank you to everyone that helped me out!
it was nice to be getting advise while working on my car...
i will definitely be back on here alot more and let you know if the car continues to run like it should.

two thumbs up!