Ignition Coils

Hello Lads,

My 197 has been misfiring like crazy the past few days. Obd2 only shows "P0300 Random/multiple cylinder misfire." I suspect one of my coils are breaking down.
I have tested the resistances and they all seem about the same at 0.6 or 0.7 Ohms. While the car is idling I removed the connection wire to each coil one by one to see if the idle changes and it has in all 4 cases. So they are working but one of them is probably too weak.
I am planning to replace them with the BREMI 20111. Has anyone used these? Had good or bad experiences? Or do you think I should just stick to OEM Renualt BERU coils which are double the price of the Bremi's in South Africa.

Cheers.
 
Have you checked the spark plugs?
You could swap the plugs/coils to different cylinders to help narrow down the cause.
Possibly injector.
 
Spark plugs have been changed and kept the OEM NGK PFR7Z-TG.
2 of my coils look like they're in bad shape so I will replace those and see if it makes a difference.
Also, I took it to an exhaust specialist. They said the heat coming off from my CAT indicates that there could be a blockage that's causing the misfire. They want to do a decat but they're charging R1400 or around 78 pounds. I have the vehicle booked for diagnostics this week Thursday with a Renault specialist so I will get them to check my CAT sensors reading also.
 
cats run hot on purpose and there is 2 in the exhaust...

usually when coils go they go dont often work then not if its the p0300 multi cylinder misfire do a search on here been loads of this reported and not one real cause can be pinned down to it
 
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Thanks Guys, it turned out to be a faulty injector. I had bought and fitted the BREMI ignition coils anyway and the car has been fine under them. Changed injector today and car is back to 100%.
Old injectors had a lot of black gunk on them, I'm scared to think what inside the cylinder looks like. Can anyone recommend some additives you have personally used to help clean out the cylinder?