check the coil pack wiring aswell mate,
the wiring that goes to the coil packs goes brittle due to the heat build up.

remove the sparkplug cover and wiggle both the wires that go to the coil packs.

even if they dont seem damged i bet you they are.
every single rs2k suffers from this and it causes all sorts of running issues.
very easy to replace and will improve things dramaticly.

if this wiring is faulty it will run very rich as it wont be sparking and buring the fuel properly and will cause emmissions to be high