So Last night I had a buddy use his aeroforce to check out my car. I was getting inconsistent reading with the vacuum..It would fluctuate from 17.9 to 18.4 then sometimes it would get to 19 than go back down to the high 17's..So I know I have a vac leak somewhere so I believe thats why the P0300 CEL light comes on...Also I was getting almost 5 degrees of knock on my 3.6 pulley that was just put on...Could the vacuum leak throw off the air to fuel and cause Kr?

The guy who tuned my car got me max timing on my stock pulley so Im guessing this is another reason why its knocking with the 3.6

 

P0300 is a random misfire. Typically from fueling issues. Your tune just might not be the best. I would go back to the 3.8 pulley if you aren't knocking on that.

When you drop a pulley you actually have to start tuning all over again for fueling and timing

 

Ive noticed that P0300 code will randomly pop every now an than when the car idles for awhile on cold starts and the rpm's an slightly bouncing but than after driving it for a few days the light goes away

Yea the guy who tuned my car is out of town for now so I'll just let the car sit and figure out where that vac leak is coming from

 

Fix your vacuum leak, that's contributing to your KR. So you're probably running 20* of timing. Either take the blower belt off, unplug your BBV, or put the stock pulley back on there for the time being. The most power can be made with lower timing (16*) and higher boost, just so you know. Get your timing back to 16, fix your leak, maybe richen the MAF a tiny bit and you should be all set.

 

I looked for any vacuum leaks and I couldnt find anything so idk what else could be causing my vacuum to fluctuate...Im thinking about taking it somewhere that has a smoke machine and have them check for leaks

 

A fluctuating vacuum reading doesn't always indicate a vacuum leak. Your description of the vacuum gauge reading sounds more like an ignition or timing problem. Instead of thinking that a vacuum leak is causing a misfire, think that the misfire is causing the fluctuating vacuum reading. A cylinder dropping (plugs/wires) would alter the rpm which in turn would cause the vacuum to fluctuate. Improper timing or air/fuel mixture would also create the same symptoms. As previously mentioned I would go back to the stock pulley or have it retuned for the 3.6 pulley. After that I think all your problems will disappear.