So the other wknd I put a Snabb intake pipe in and took out the old, replaced some hoses and installed a boost gauge. I cleaned the PTC nipple as well. This will happen randomly but usually after freeway driving when I roll to a traffic light. The RPMs will drop slightly and the car will do a slight shudder and then everything is fine again. I didn't know if it was a vaccum leak or an Idle control valve. Nothing was changed except for putting an added small silicone hose over the small hose that connects to the PTC nipple (the thinner hose) because it would not reach the connection on the nipple connected to the Snabb and a small piece of the black pipe has cracked off (have read this has happened to numerous people on multiple forums). I do not believe that is the issue, but could possibly be a vaccum leak off one of the lines off of the snabb by the TCV. Any help would be greatly appreciated. It does not happen all the time, but has 3 or 4 times since last weekend.

MAF, MAP, TCV have been replaced recently.