[Mrunn]

Good morning,
First time poster, thank you in advance for any help/advice!

I have a 2014 i30 trophy, 5 door hatch, 1.8L petrol.

Problem: occasionally very rough, jerking idle at start up and then occasionally dying.

Question: Thinking spark plugs, fuel filter or ignition coil may be to blame? What do to think? We are looking to fix this ourselves where possible.

Details: happening more frequently of late, car turns on but idles really rough, sort of jerking when really bad. Car tries to rev itself up and occasionally that fixes the issue, sometimes I'll rev the engine and that also fixes the issue. The other day, I let it sit for 20seconds doing this and it died and struggled to start up again. If I put the car into drive and quickly start driving, it drives fine and no noticeable issues. It may be happening more frequently after short trips but can't say for sure.

[Sybrena]

I had the same issue unresolved for 7 years, finally had a mechanic discover the fuel pump was incorrectly installed (back to front).
I experienced the same issues in inconsistent occasions.
Low revs upon initial start up( warm or cold) spiking after approx 8 seconds and then stalling.
I've also had the car enter limp home mode while driving losing power, steering and breaks.
In addition I experienced fuel fumigating the cabs interior, an unresolved fuel leak and inconsistent fuel consumption.
This was only diagnosed after a major service that called for the fuel pump and filter replacement-makes sense with how bad the smell is in the cab, being located under that rear passenger seats.
Maybe my experience may offer a new point to investigate.