My Evo 3 16g has horrible lag and it isn't getting any better. I'm seeing 15 psi @ 5000 rpms. I've done a boost leak test and so far the only leak I hear is a small one from the throttle body shaft seals. I am also blowing dark smoke if I rev the engine. I did a compression test and got good numbers. I checked the shaft play on the turbo and the side to side seemed like it moved a descent amount. The fins where not very smooth when I was feeling them either. The turbo is very loud when it does spool (by this I mean I can hear it pretty well over my full 3 inch exhaust). Think its a blown turbo?

Yep. And that's probably where alot of your oil is going.. but how's the in and out play and define a "decent amount" of side to side play.

There didnt seem to be any in and out shaft play. The side to side was probably like 1-2mm? Thats a very rough estimate.

Well, given what you said, there is a good chance it is blown (or is going). However, my Evo III is VERY loud as well, and it is brand new. It masks my 3" exhaust (no cat) as well. Just as an FYI.

Dark smoke as in black or blue?
White - coolant
Black - fuel
Blue - oil

1mm is very small in terms of shaftplay. But any play at all isn't a good sign. Look at the exhaust turbine. Oil?

I'm starting to think it was maybe black smoke I was seeing. It just seems wierd that those throttle body shaft seals (the only leak I really can hear left) is causing this turbo to get full boost at 5k rpms when it should get it at 3k.

Look at your wastegate. Is it stuck open? That's the only other thing I can really think of.

If you have ANY boost leaks, it will cause you to run rich. Richness will cause black smoke and also, if it's REAL rich, will cause you to pull timing and your car will feel like a dog.
Fix your boost leaks and tune it.
A small amount of shaft play is acceptable but try to keep an eye on it. A car that has boost leaks will also cause the turbo to work that much harder and your play WILL get worse.

Originally posted by RST95eclipse
Look at your wastegate. Is it stuck open? That's the only other thing I can really think of.

Thought of the wastegate idea, but I don't think this would cause the richness...just the slow spool. Im going to check it today none the less.

I checked my wastegate and the arm isnt holding it open at all...as a matter of fact its a pain to get the arm back on the rod because the arm is like a mm too short. Back to the drawing board.

Well, I did a better check on the turbo today. Although boost leaks and running rich are most definitely my problem, the turbo did have scrape marks on the bottom of the inlet housing (I dont know if thats the name for it?). When I spun it, it spun veery nice and perfectly free, however if i pushed down on it and spun it I could hear it very lightly scraping the bottom once every 360 degrees. Very faint.

Originally posted by burntheblobs
Well, I did a better check on the turbo today. Although boost leaks and running rich are most definitely my problem, the turbo did have scrape marks on the bottom of the inlet housing (I dont know if thats the name for it?). When I spun it, it spun veery nice and perfectly free, however if i pushed down on it and spun it I could hear it very lightly scraping the bottom once every 360 degrees. Very faint.

(Compressor housing) That very faint scraping could be your
"very loud spooling" at the RPM's the turbo really spools at.. ahem.. ~100,000rpm's.

those shaft seals are fairly easy to do, set aside a few hours, and the right screw driver (the shaft screws are f;cking tight) and it did make a big difference for me.

Originally posted by kelvinb1
those shaft seals are fairly easy to do, set aside a few hours, and the right screw driver (the shaft screws are f;cking tight) and it did make a big difference for me.

Yeah but something got in my turbo compressor and it looks like the compressor blades are chewed up a little bit. =(. I think it might be time for a new turbo. Sigh. Stupid 16g.

while you are doing the turbo, i highly reccomend doing the shaft seals also. the seals they now reccomend are like 4 bucks a piece, and the others (i used) were like 20 cents a piece. no difference.

Originally posted by kelvinb1
while you are doing the turbo, i highly reccomend doing the shaft seals also. the seals they now reccomend are like 4 bucks a piece, and the others (i used) were like 20 cents a piece. no difference.

Picked up two o-rings for them today. Basically I found 3 leaks on the intercooler piping, 2 throttle body leaks (gaskets and o-rings), and the compressor outlet gasket leak. So thats 6 boost leaks on the intake side. I also suspect my intake manifold gasket might be leaking. NOW, when I was taking my turbo off my manifold to turbo gasket came off in 3 peices, and one of the studs on the exhaust manifold was loose...had to tighten back in. That on top of a half blown turbo, Im suprised I got 15psi @ 5000rpms ha.

what i do is test everything seperate, its alot easier to pinpoint everything. i have hard pipes, so testing those are really no big deal, but if you take the ic off and test it, also test at the tb elbow and test there also. good luck!