What could be wrong with my 1993 Mitsubishi Wagon?

This means that you have to change plugs and wires to get a more complete, combustion from your car , you have bad emissions, and heres what it really means , maybe to under stand it in terms, of what they mean,
a method and an apparatus to reduce NOx
emissions in the exhaust gas from installations that form NOx as a result
of combustion processes, in which the NOx decomposition occurs in the
temperature range from approximately 450° C. to approximately
850° C. and in an oxidizing atmosphere with a fuel-air ratio
(Lambda) is greater than approximately 1.

2. Background Information

Nitrogen oxides, NOx, including at least nitrogen monoxide, NO, and
nitrogen dioxide, NO2, are formed in essentially all industrial
combustion processes from atmospheric oxygen, atmospheric nitrogen and the
compounds containing nitrogen in the fuel. At combustion temperatures
above about 1600° C., with sufficiently long dwell times of the
combustion gases in the flame, the essential product formed from the
molecular nitrogen can be nitrogen monoxide, NO.in other words you are putting out a lot of bad gas into the air instead of burning it, the spark , is to cold, and a lot of bypass is going out the tailpipe

The smog place you took sucks..all you need to do is use super unleaded gas and run it for about 100 miles..that should lower your emision