94 dx , did search most like the cat. converter

1st test=fail
15MPH - HC=max=72, meas=51 CO=max=0.59 meas=0.19 NO=max=731 meas=1163 FAIL
25MPH - HC=max=44, meas=17 CO=max=0.59 meas=0.05 NO=max=798 meas=548 PASS

CHANGE CAT.

2nd. test=fail
15MPH - HC=max=72, meas=4 CO=max=0.59 meas=0.05 NO=max=731 meas=216 pass
25MPH - HC=max=44, meas=4 CO=max=0.59 meas=0.01 NO=max=798 meas=1301 FAIL


guys help out, what should i do next?

 

Check your fuel system. Replace the filter if it is old or borrow a pressure gauge and check the pressure with and without the regulator vacuum hose connected. You may also want to check your ignition timing.