I took my car(87 5th Ave with a 318(5.2L) v8) in for an emission test and it
failed miserably

Here are the results:

ASM2525 Test
Curb Idle Test


Limit Reading Result
Limit Reading Result
HC ppm 83 197 FAIL 300
504 FAIL
CO% 0.46 0.16 PASS 1.50
6.76 FAIL
NO ppm 893 1220 FAIL N/A
N/A N/A
RPM 1092 VALID RPM
854 VALID
Dilution 13.8 VALID
Dilution 17.2 VALID


What are the possible causes and cures? TIA

P.S. It passed the Gas Cap Pressure Test and Fuel Filler Integrity Check