Won't go over 3000rpm, Black Smoke, Rough

[Closed Loop]

Car Info:
1990 Talon TSI AWD - Bone Stock
103,000, has been sitting sinse August 2004
Was given to me by colleague to free up his garage, so I don't know the history, but he said it ran better back in August.

Issue Info:
There is an obvious exhaust leak that can be heard as well as seen. Idling on the driveway leaves a black mark on the concrete with some oil. The mark occurs just slightly back from straight down the exhaust manifold. When attempting to rev the engine it won't go over 3000rpm and black smoke comes out from under the hood. When driving, if throttle is over ~10% the stock calculated boost gauge reads full boost and the vehicle bucks and is rough, and again the engine won't go over 3000rpm.
Not having alot of experience with Turbos I'm at a loss, is this just a matter of bad plugs/wires/leaks, or is it a much more serious problem? Any help/ideas would be appreciated.

 

[johnk]

Try a boost leak test and replace what ever gasket is leaking all the black smoke uinder the hood.

The stock boost gauge is garbage and shouldn't be used to tell actual boost.

 

[PaleDSM]

Sounds like a big boost leak. Pressurize the intake with a leak tester and fix 'em up.

 

[Tevenor]

Make sure his maf is hooked up.

 

[Closed Loop]

Thanks for the responses, I'll do a leak test this weekend and hopefully get it figured out. I was worried that it may be something serious, but a leak can be fixed with ease.

 

[944g63talon]

i'd say make sure the maf is hooked up also.