cat. smell when hot, gas milage

[hihosilver]

I smell the cat. converter smell when I shut it off, car is 86 300 e with 115000 miles, I just got the car a couple of months ago, its very different from my diesel in some ways. changed plugs wires dist cap and rotor, fuel filter, plugs looked real dirty with lots of build up, cap was pretty burned but milage did not change, getting 18 to 20 around town and road, also using a quart of oil every 3 tanks of gas, car only driven 1500 miles in the last year before I bought it