Huge Emission Problems

Up here in BC we have a program of wonders called air care. Most people who know the system can tell i'm being sarcastic. Anyways my 88 5.0 is having lots of problems with hydrocarbons on idle. Was wondering if anyone knew what could be wrong and if there is any tricks to lower emissions. My rating was 455ppm and you're allowed 88ppm. Also it seems there is a slight missfire on idle any suggestions?

my 89 scores as an ultra low emissions vehicle. this is because it has a HUGE exaust leak just before the mufflers. I have a whole new exaust system ready to go, but i want to wait for my next smog check before i put it on. :evillol:

i would advise you to get a tune up first of all. getting your timing right is beneficial to more than one area of your car.

How old are the 02 sensors?

o2 sensors have just recently been replaced, have done a full tune up, new wires, cap, rotor, plugs.