What can it be?1995 Aurora

[Hesam]

Since about a year ago My 95 Aurora had been misfiring. I changed 1 coil, changed spark-plug and wires with AC-Delco package, it got better but still wires seemed weak and malfunctioned after a while, also didn't pass emissions. Then I installed NGK-iridium plugs and my emissions got better but still HC level is about 10-20 over maximum to pass. Now car runs smooth and my RPM gauge arrow doesn't shake at all, car cools down on the freeway but when car stops in traffic it seems to get too hot (225-250 degrees).
Something is causing the extra heat and high HC level of emission, what can it be?

[dsatt12]

I've heard from my mechanic normal life expectancy on an oxygen sensor is around 100,000 miles. You have 2 fyi. Dunno what you've at for miles on your car. Your catalytic convertor is also supposed to break down residual hydrocarbons as well as convert NOx into nitrogen and oxygen. Could be that yours is a little fouled. I seem to recall no shortage of approved fixit shops out there in CA just begging to take thousands of your dollars once you run afoul of the smog police. I'd say you're about going to have to let them have at it again now that you've failed your inspecion a couple of times.

A cheap option in between is to try some fuel system cleaner like Chevron Techron. A lot of times it doesn't seem to do much, but it's like $20 and you don't need much.

Your temps sound normal to me. It's what we get for not having a grille. I think I read the cooling fans don't even come on until 220.

[Aurora95]

take your car to a shop and have them check the evaporative canister it if it is leaking all the time it will cause your to fail emissions with high HC ususally you can just plug the ports on the canister and you will pass