Vacuum leak? or something worse?
 

After changing out my plugs and driving my car for the first time since late October, I noticed something different.

During start up I get about 10-15 seconds of light smoke. Once warmed up, my idle jumps between 500 and 800 RPMs and the vacuum jumps around between 9-14 Hg and it feels like it's going to kill. If I rev it up to 1100 RPM my vacuum remains constant at 16 Hg. There is definitely not any power loss which makes me think it's just a vacuum leak somewhere. Over this winter I put in a Greddy Pulley kit and elimated the Airpump which may be a contributing factor to this weird problem. (Planning to get a PFC to get the fuel mixture straightened out)

I did check the Map sensor and it's tightly connected.

Just wondering if people think it's a leaky hose somewhere or if it's a sign of something worse. Let me know what you guys think. I want some ideas/opinions before I take it in for a compression check or a hose job. BTW the car has 51k miles on the original engine. Mods are below.

it could be the fuel pressure, my car idled between 500 and 1200 rpms and I was told that it could be the fuel pressure.

I didnt have a fuel pressure guage so i was going to borrow brain@bnr's and on my way there a coolent seal or water seal blew and the motor is being rebiult as of now.
My car smoked really bad after idling for maybe 10-15 seconds, the motor had 4k miles on it. Good luck.
Im not saying that was the problem or anything, i just dont know if it was the fuel pressure or what.