I purchased a EGR delete kit with a new Y-Bridge and hot side pipe. I disconnected the batteries and began working. While trying to complete the project and juggling two jobs, i finally finished after about 2 weeks. (i know, it took a while, but I'm a firefighter also, so I'm not always home at the end of the day.) When i started the truck back up it took a few seconds of turning the engine over for it to finally start up. Im estimating about 10-15 seconds. When it started I pressed the throttle a little and a knock started. If i turn the truck off and let it sit, the knock will not be there after start up, but if you hit the throttle, it will begin again. this knock has never shown itself before. Any ideas?