Did I blow my Turbo?

[ClassicalBor]

I was running my car pretty hard for a while yesterday but nothing extreme. I have been running the Stock T-25 at 16psi for the last 2.5 years, no problems. As of last night when I give it enough throttle to spool up, anything past 4-5psi and it HICCUPS... chokes... and the blow off ... blows itself off... like it can't handle the boost. I've also noticed looking under the hood that it appears some dark black soot/grime is now on the exit port that leads to my intercooler piping.

I plan on taking the piping off tomorrow to look directly at the Turbo itself but does this sound like a potentially blown turbo?

My car also idle's strangely low now for a few minutes or every once in a while when i put the clutch back in to roll to a stop. Im wondering if it has something to do with the MAF and air compensation because the turbo is messed up. It did stall one time, but only once.

I've looked over a few threads but each person had semi-different symptoms.

Any Ideas guys??

Thanks.

 

[jking29]

Have you tested for a boost leak yet? Also check the turbo for shaft play. Post back after you get those done.

 

[ClassicalBor]

I previously had a boost leak before, replaced all my silicone hoses, and its not acting like a boost leak like i previously had. When i had a boost leak i would just run slow, rich, and max about 9 - 10psi.

I will know tomorrow though, Im gonna get down and dirty tomorrow taking the bumper and hoses off to check the remaining hoses for leaks and looking at the turbo itself for shaft play, etc.

 

[ClassicalBor]

Its been raining all day so I been clearing out my garage to eventually get it in there so I can get down near the turbo itself. But I think just having the car on and idling and then opening the throttle a few times.. (low rpm, no more than 3,000rpm maybe) sounds like there is a hissing noise coming from near the intake manifold. Somewhere down between where the fuel injectors sit and the manifold itself. Couldnt really get a good look or feel any air leaks down in that area but is it possible to have a leak there?

Also, if I were to use soapy water to check for leaks WITHOUT pressure testing the system... will i produce enough boost/power just by revving the engine a few times to see any bubbling if theres a leak where I sprayed it?

 

[jking29]

There are seals, called insulators, around the base of the injectors where they go into the head. They get hard with age and numerous heat cycles and cause boost leaks. If you can hear a hiss from vacuum, you definitely need to do a correct boost leak test. That big of a leak will make a night and day difference in how your car will run. And, no, spraying soapy water and revving the motor will not work. You need positive pressure blowing out to make bubbles, you won't build boost just revving it. If you don't have a correct blt tester, you need to make one or buy one. Doing a blt is routine maintenance and should be done on a regular basis with these cars if you want it to run right.

 

[ClassicalBor]

You said hiss from vacuum... and i JUST realized while driving the car that while im in neutral just coasting... 30 or 40 mph on my way home... that my boost gauge is fluxuating in the vacuum area.. normally it would remain around 15 vac while just neutral coasting... it fluxed down to 10 and showed a lot of movement that it normally never does.

If I have a leak up by the manifold, could it just be the possibly the gasket around the throttle body?

Understanding a boost leak is easy, but im not exactly sure what to think when I have a vacuum leak. Any other places i might want to start checking besides around the fuel enjectors or throttle body?

 

[jking29]

If it leaks vacuum, it will become a massive boost leak under boost. Again, you need to do a proper boost leak test. Spray soapy water all around the manifold, throttle body, injectors, egr, vacuum lines, basically everywhere that sees boost. If you can hear it, it shouldn't be too hard to find.

 

[ClassicalBor]

yep, I went out today to buy a few things so that i can do a boost leak test, letting the car cool a bit right now (plus eating for father's day) then im gonna get on it.

But i think its getting worse now too... just on my way home it was bogging a lot without even hitting boost this time, almost felt like a cylinder misfire. On top of that it kept wanting to stall out. I had to keep giving the car a bit of gas coming to stops and waiting to pull out from a stop to prevent me from stalling so I could get the car home in my driveway. Possible symptom of the boost leak just getting larger due to the fact ive been driving on it a bit?

 

[ClassicalBor]

Finally had the time to get out there all day and look for leaks. Made a boost leak tester but didnt really have a good compressor to test it. Found a leak on the top intercooler piping leading into the top of the IC. Replaced that, drove it... ran fine for a few minutes then acted up again. Found that another clamp on a different silicone hose on the upper IC piping was loose and not clamped properly. Fixed that too, now its seems to run fine, held boost fine, at 15psi on full throttle... will give it the rest of the week to see how it does i guess.

Looked at the turbo, had no shaft play, inducers spun fine.

 

[awdwhip]

Good to hear you fixed your leak but another thing you wanna do is once you have driven around for a bit, pop the hood and tighten the t-bolt clamps down some more since the couplers at that point will be nice a hot and will allow your clamps to tighten down a bit more