Hello I have a 2000 2x4 that recently as I was driving lost very small amount of power. I was going 70 when it happened. I noticed that it was shaking very little while sitting still. I plugged in and it said bank 1and2 lean also misfire cylinder 1. I swapped plugs cylinder 1 for 6 and still had the miss fire. The coil is an NGK two years old. Three weeks later the codes now say 1 and 2 lean still and a vacume leak but no misfire code. The truck is still misfiring though. Also now I smell eggs and the exhaust is white longer and more than normal..... any ideas please help thanks.