So after having a good nose around the entire bay I spotted these wires to the ecu, stripped to bare cable in places. As far as I can see it's only the two wires. Would this be a cause for running on two cylinders?
Was the loom tape damaged and has the copper in the wires worn down?
It could be that some one has bared back those wires while fault tracing.
I have similar wear to my loom in the same area, i think its just Renaults poor loom planning and your engine vibrations grazing it repeatedly over time
I just insulated both wires separately with electrical tape then wrapped a nice black bandage around them all again.
Edit: Tried cleaning TDC sensor? seems common for them to get muckied up.
right hand side just above gear box, two bolts on a curved bracket, remove and just pull i believe.