if its out a tooth, yea, that has to be fixed.
But like Brett said, EGR and lean. Those are two of the biggest NOx fail causes.
The EGR does nothing to harm performance, in fact it may actually help with part throttle tip in knock. It did for me. No reason to get rid of it.
And you have plenty of room to add some fuel. Too lean is no good for aircare. Of course don't go nuts, but you have boatloads of room on CO(rich indicator). HC is not normally caused by overly rich conditions, unless you go slobbering drunken rich. HC is unburned, not partially burned, hydrocarbons, so its mostly caused by misfires.
The other thing to look at is timing. If your base timing(ignition) is off, even by a bit, you will get NOx, (and knock without methanol/water), and timing also effects HC to a fair amount.
But get that EGR back in, add a bit of fuel, make sure its in closed loop throughout the whole test, and check the timing, both base and in your maps. Remember that the 'Link behaves in some ways like a piggy back system, so know that pulling fuel can add timing(I think so anyways, from what I've read)
As for your timing belt, just look at the marks, upper cover off. If its off even one tooth, your HC would be rediculous.
