Possible misfire? NEED HELP!

[millertime6009]

1990 2.0 tsi awd

Ok first of all my car idles at 1k but is very rough. If I press the brake while stopped at a traffic light or something it will die unless I heel-toe it to keep the revs up. Also when I floor it right at 4k it bucks and loses power. Boost hits 10psi right at 4k seems like it wants to keep going but gauge needle vibrates rapidly from 10-11psi. Going to work this morning I heard a hissing noise coming from what seemed like the driver side engine bay leading me to believe it is a vacuum leak. I dont know I just bought this thing and Im really frusterated please help.

thanks

 

[Lofty]

Check for boost leaks.
Test your ISC.
How are your plugs/wires. Are they gapped correctly?

 

[Spln_Hrd]

Check for boost leaks.
Test your ISC.
How are your plugs/wires. Are they gapped correctly?

^^^^ what he said.

 

[millertime6009]

sorry for the newb question but whats the ISC?

 

[millertime6009]

Never mind figured it out... Idle Speed Control. I set the screw and when I attempt to get it to 750 it just dies... anything under 1.2k at idle the thing eventually cuts out.