sleeves

1993 ZX Furio 1.8-8V: Exhaust was blowing last week so, after a couple of days the misfire began and, so did the rotten smell of eggs(CAT; by its sell by date) At the time thought this was causing the misfire. Had the CAT and middle section renewed at a cost of £250 to no avail. Plugs, spark,idle valve,and fuel filter all been checked out with no problems but the misfire continues. Any further help much appreciated.