Thanks for your replies Jamie but the exhaust is standard again now and this still didn't sort the problemAlso luke as your exhaust isn't standard the emission light will always stay on mine always did as well and you'll always have the error code reading of emissions below threshold.
Mines doing this now
When idle sounds rough, engine management light flashes and my cheap code reader is saying misfire cylinder 4. Once it gets going the engine management light will go off but every so often it will feel sluggish. I've not tried anything yet to sort it so open to ideas!
I'm going for injector too been for a diagnostic and and come up that was the problem so got one ordered and will fit it once arrived hopefully that end of it
So did your problem went a way after changing injectors?
My clio 182 has same problem.
Yeah all new injectors solved the problem for me mate never happened again afterwards!
After changing Coil and one Injector for 4th cylinder my EML went a way finally THX