I recently replaced the head gaskets in my (NEW TO ME) 05 duramax 2500. I now know what to look for when i buy. This is my first diesel so please be patient. I got it all back together. It has All new injectors new seals new left lower valve cover. ARP bolts in heads and exhaust. New glow plugs. I had adjusted the valves to the best of my knowledge (youtube) I had the heads resurfaced and was told i had to adjust the valves. Anyways my issue is when i start it i hear a knocking noise sometimes sounds really bad sometimes not so bad. I am currently not driving it due to the noise. I had originally drove it after the repair and did not hear the noise i hear now. Only difference i can think of is it is a lot colder now then it was when i originally started it. If i try and drive it it idles really rough until i give it a bit of gas but still seems a little shuttery. The guy before me had efi live on it and i know on the later models new injectors could make a similar noise. I am not getting a engine light at all. It does smoke at startup (white) did that right after i fixed it but went away after a few minutes. Wasnt to worried considering what had just been done to it. Could i have adjusted the valves wrong and that is causing this. I need this truck for work but am largely out of money and patience. Does anybody have any ideas? I am suspicios of a passenger side exhaust leak but again didnt have problems when i orginally drove it 12 miles and parked it. I did have coolant leaks but i just got new seals and will replace this week. At a loss of what this could be and just made my 2nd payment.