Your Dodge Dakota failed the smog test with very high HC emissions. Hydrocarbon (HC) is basically raw fuel, otherwise known as gasoline. The main reason your Dodge Dakota would fail the smog check because of high HC would be defective spark delivery, but the fuel system has a lot to do with it as well. A "rich" or "lean" fuel mixture would contribute to high HC as well. Since having replaced your Dakota's brake booster, we must recommend that you ensure the brake booster is not creating a vacuum leak; since it relies on manifold vacuum to assist brake function. A vacuum leak will cause high HC, especially at idle.
Begin with inspecting your Dodge Dakota's ignition system, ie. spark plugs, wires, distributor, and ignition timing. Make sure the spark plug wires are affixed firmly. If everything looks ok, move on to the more complicated inspection of the fuel delivery system, ie oxygen sensor (s), engine coolant temperature sensor, mass air flow sensor. These components will require some auto emissions know-how and proper inspection tools. It is best left up to an experienced smog check technician.
Follow the link below for a full list of High HC Causing Problems:
What Causes High HC?
