Help. I failed Nj emissions test

[noraboeff]

I failed NJ emission test -
CO Standart 0.71 Reading 8.88 and
HC Standart 128 ,Reading 162
I already changed the spark plugs and wires , the distribution cap, and PCV valve .I added fuel injector cleaner and additive to the oil for cars over 50000 miles .( Engine oil changed as of yesterday also) When the car is on idle the engine works fine, but while I'm driving, I can feel that the engine shakes a bit and runs rough and coughs, shakes.
Can you please tell me where I should look for the problem, and how to pass .
Please help !!!