Just another update on this. I’ve been trying so many things to fix the rough feeling idle.
Mechanic checked over my car thoroughly today and said the issue isn’t mechanical (although I’d changed spark plugs, leads and coil).
The issue is the top engine mount. Apparently it’s a gas type and mine is completely flat (should have a gap in between). Mechanic says as soon as I fix this the idle issue will be resolved. He’s quoting $200 to fix (which I don’t think is so bad).
The issue is that due to the bad mount the vibration is travelling through the car making it feel like a bad idle, but the engine is perfectly fine.
Cheers.